Pub Date : 2020-11-13DOI: 10.2174/2211550109999201113101040
S. Dash, Sabita Pattanayak, Barsarani Jena, M. K. Panda, Y. Singh
Xanthine oxidase (XO) is an essential enzyme in catalyzing the hydroxylation of hypoxanthine to xanthine and uric acid in the kidney. Excessive formation of uric acid can lead to hyperuricemia (HUA), a condition caused by excess uric acid contamination in the blood. HUA is responsible for various diseases in the body, such as gout, cardiovascular, and renal failure. It is also associated with numerous inflammatory diseases and their metabolic pathways, including tumors, chronic hypoxia, renal injury, and hypertension. XO is a superoxide producing enzyme usually confined to lungs, liver, and blood serum. Blood assay and diagnostics for XO help in a better understanding of its associated diseases in the human body. The mechanism of how XO is released in the bloodstream is a matter of debate in medical science. In the current review article, we comprehensively discussed the role of XO in human health, inhibitors, and their regulation, isolation, and extractions of inhibitors from plants, types, and their activities towards the human health perspective are described.
{"title":"Xanthine Oxidase Perspective in Human Health","authors":"S. Dash, Sabita Pattanayak, Barsarani Jena, M. K. Panda, Y. Singh","doi":"10.2174/2211550109999201113101040","DOIUrl":"https://doi.org/10.2174/2211550109999201113101040","url":null,"abstract":"\u0000\u0000Xanthine oxidase (XO) is an essential enzyme in catalyzing the hydroxylation of hypoxanthine\u0000to xanthine and uric acid in the kidney. Excessive formation of uric acid can lead to hyperuricemia\u0000(HUA), a condition caused by excess uric acid contamination in the blood. HUA is responsible\u0000for various diseases in the body, such as gout, cardiovascular, and renal failure. It is also\u0000associated with numerous inflammatory diseases and their metabolic pathways, including tumors,\u0000chronic hypoxia, renal injury, and hypertension. XO is a superoxide producing enzyme usually\u0000confined to lungs, liver, and blood serum. Blood assay and diagnostics for XO help in a better understanding\u0000of its associated diseases in the human body. The mechanism of how XO is released in\u0000the bloodstream is a matter of debate in medical science. In the current review article, we comprehensively\u0000discussed the role of XO in human health, inhibitors, and their regulation, isolation, and\u0000extractions of inhibitors from plants, types, and their activities towards the human health perspective\u0000are described.\u0000","PeriodicalId":10850,"journal":{"name":"Current Biotechnology","volume":"43 1","pages":"1-8"},"PeriodicalIF":0.0,"publicationDate":"2020-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82224532","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-10-27DOI: 10.2174/2211550109999201027201433
Y. Saravanan, B. Devaraj, Nithesh Kumar Velusamy, Pooja Shree Soundirarajan, Kumaravel Kandaswamy
Phytochemicals such as tannins, alkaloids, flavonoids, and peptides have been found to have antimicrobial activity against a variety of bacterial strains. However, optimal extraction procedures for these phytochemicals and their efficacy evaluation against certain pathogenic bacterial strains remain unclear. Therefore, in this study, phytochemicals from Leucas aspera (L. aspera) and Dahlia pinnata (D. pinnata) were extracted by hot and cold extraction methods using water and methanol as solvents. In addition, antimicrobial activity of L. aspera and D. pinnata extracts against bacterial strains such as the gram-negative Escherichia coli (E. coli) and the gram-positive Enterococcus faecalis (E. faecalis) was performed by Minimal Inhibitory Concentration (MIC) and CFU quantification assays. The majority of the phytochemicals such as protein, carbohydrate, tannins, flavonoids, phenols, and saponins were present in our extracts, but steroids were absent in the extract. Protein, tannins, flavonoids, phenols, and saponins were present in both L. aspera and D. pinnata. The yield of proteins was high (1.990 ± 0.091 mg/ml) in methanol extracts of L. aspera and low (0.199 mg/ml) in aqueous extracts. However, the yield of tannins was high (1.713 ± 0.079 mg/ml) in methanol extracts of D. pinnata and low (0.528 ± 0.136 mg/ml) in aqueous extracts. The MIC of D. pinnata extracts were found to be 200 mg/ml for both E. coli and E. faecalis. However, the L. aspera extracts had an MIC of 100 mg/ml and 200 mg/ml on E. coli and E. faecalis, respectively. This article demonstrated the potential use of phytochemicals as novel antimicrobial compounds against bacterial infections.
{"title":"Phytochemical Extracts of Leucas aspera and Dahlia pinnata Exhibit Antimicrobial Properties in Escherichia coli and Enterococcus faecalis","authors":"Y. Saravanan, B. Devaraj, Nithesh Kumar Velusamy, Pooja Shree Soundirarajan, Kumaravel Kandaswamy","doi":"10.2174/2211550109999201027201433","DOIUrl":"https://doi.org/10.2174/2211550109999201027201433","url":null,"abstract":"\u0000\u0000Phytochemicals such as tannins, alkaloids, flavonoids, and peptides have\u0000been found to have antimicrobial activity against a variety of bacterial strains.\u0000\u0000\u0000\u0000However, optimal extraction procedures for these phytochemicals and their efficacy\u0000evaluation against certain pathogenic bacterial strains remain unclear.\u0000\u0000\u0000\u0000Therefore, in this study, phytochemicals from Leucas aspera (L. aspera) and Dahlia pinnata\u0000(D. pinnata) were extracted by hot and cold extraction methods using water and methanol as\u0000solvents. In addition, antimicrobial activity of L. aspera and D. pinnata extracts against bacterial\u0000strains such as the gram-negative Escherichia coli (E. coli) and the gram-positive Enterococcus faecalis\u0000(E. faecalis) was performed by Minimal Inhibitory Concentration (MIC) and CFU quantification\u0000assays.\u0000\u0000\u0000\u0000The majority of the phytochemicals such as protein, carbohydrate, tannins, flavonoids,\u0000phenols, and saponins were present in our extracts, but steroids were absent in the extract. Protein,\u0000tannins, flavonoids, phenols, and saponins were present in both L. aspera and D. pinnata. The\u0000yield of proteins was high (1.990 ± 0.091 mg/ml) in methanol extracts of L. aspera and low (0.199\u0000mg/ml) in aqueous extracts. However, the yield of tannins was high (1.713 ± 0.079 mg/ml) in\u0000methanol extracts of D. pinnata and low (0.528 ± 0.136 mg/ml) in aqueous extracts. The MIC of\u0000D. pinnata extracts were found to be 200 mg/ml for both E. coli and E. faecalis. However, the L. aspera\u0000extracts had an MIC of 100 mg/ml and 200 mg/ml on E. coli and E. faecalis, respectively.\u0000\u0000\u0000\u0000This article demonstrated the potential use of phytochemicals as novel antimicrobial\u0000compounds against bacterial infections.\u0000","PeriodicalId":10850,"journal":{"name":"Current Biotechnology","volume":"117 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89859342","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-10-26DOI: 10.2174/2211550109999201026090415
Narges Malek-sabet, M. Masoumian, A. Aramvash
As an effective alternative to conventional suture techniques, topical hemostatic agents are widely used to control bleeding and close wounds in surgeries. This study was conducted to evaluate the efficacy and safety of a novel hydrogel hemostat that is easy to use in an applicator under normal conditions according to ISO 10993. The safety of DexGel, a natural surgical hemostat containing mainly dextran that is an effective hydrogel in bleeding stop, was evaluated and compared to that of AristaTM. APTT test and cytotoxicity tests (i.e., MTT assay, Crystal violet assay, and qualitative estimation) were carried out for considering safety in skin sensitization in a guinea pig model. This study has shown that DexGel does not cause any noticeable sensitization such as edema and erythema or observable toxicity for skin and does not disturb the coagulation process. In addition, cytotoxicity results approve its safety for cell survival. It can be concluded that the safety and efficacy of DexGel (5 g) are comparable or even better to that of AristaTM, which is a commercial and frequently used hemostat, and the lack of skin irritation and toxicity for DexGel alleviates initial safety concerns for products based on these polymers and oligomers.
{"title":"Evaluating the Safety and Toxicity of a Modified Dextran-based Biopolymer as a Hemostat","authors":"Narges Malek-sabet, M. Masoumian, A. Aramvash","doi":"10.2174/2211550109999201026090415","DOIUrl":"https://doi.org/10.2174/2211550109999201026090415","url":null,"abstract":"\u0000\u0000As an effective alternative to conventional suture techniques, topical hemostatic\u0000agents are widely used to control bleeding and close wounds in surgeries.\u0000\u0000\u0000\u0000This study was conducted to evaluate the efficacy and safety of a novel hydrogel hemostat\u0000that is easy to use in an applicator under normal conditions according to ISO 10993.\u0000\u0000\u0000\u0000The safety of DexGel, a natural surgical hemostat containing mainly dextran that is an effective\u0000hydrogel in bleeding stop, was evaluated and compared to that of AristaTM. APTT test and\u0000cytotoxicity tests (i.e., MTT assay, Crystal violet assay, and qualitative estimation) were carried\u0000out for considering safety in skin sensitization in a guinea pig model.\u0000\u0000\u0000\u0000This study has shown that DexGel does not cause any noticeable sensitization such as edema\u0000and erythema or observable toxicity for skin and does not disturb the coagulation process. In addition,\u0000cytotoxicity results approve its safety for cell survival.\u0000\u0000\u0000\u0000It can be concluded that the safety and efficacy of DexGel (5 g) are comparable or\u0000even better to that of AristaTM, which is a commercial and frequently used hemostat, and the lack of\u0000skin irritation and toxicity for DexGel alleviates initial safety concerns for products based on these\u0000polymers and oligomers.\u0000","PeriodicalId":10850,"journal":{"name":"Current Biotechnology","volume":"42 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78545644","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-10-26DOI: 10.2174/2211550109999201026091132
A. Ilangovan, Venkatesh Raghu, R. Venugopal, Narayan Vijay, Yellapa Yellasamy, Akshaya Venkatramanan
Novel Therapeutic Phytochemical studies are based on the use of plants in the production of drugs. The present study was carried out to perform the screening of phytochemicals and their quantitative analysis to assess in-vitro antioxidant activities of the hydroethanolic leaf extract of Caesalpinia Pulcherrima. FT-IR and GC-MS analyses of hydroethanolic leaf extract of Caesalpinia pulcherrima were also conducted. The investigation of qualitative and determination of quantitative phytochemical analysis were performed using standard procedures. The total alkaloid, flavonoid, phenols, and tannin content were determined spectrophotometrically. DPPH (2,2-Diphenyl-1-picrylhydrazyl) free radical scavenging activity and ABTS (2,2’-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)) free radical scavenging activity of hydroethanolic leaf extract of Caesalpinia pulcherrima were estimated by standard protocol. The identification of functional groups was made using plant leaf extracts by FTIR and GCMS. The hydroethanolic leaf extract of Caesalpinia Pulcherrima gives positive results for alkaloids, flavonoids, phenols, carbohydrates, tannins, amino acids, and proteins. The content of total alkaloids, flavonoids, phenols, and tannins varies from 8.4 AE/g, 3.3 CE/g, 2.9, and 3.2 GAE/g, respectively. The antioxidant assay and IC50 values were found to be DPPH (43.3μg/ml), ABTS (46.1 μg/ml), and ascorbic acid (41μg/ml), respectively and concentration ranging from 20 to 100 μg/ml. Functional groups were also identified using the extract by FTIR and GCMS. From this work, it can be concluded that the presence of phyto-component makes the plant useful in the treatment of various diseases. As such, it has been found that the hydroethanolic leaf extract of the plant contains more components and is beneficial for further research.
{"title":"Evaluation of In-vitro Antioxidant Potential, and Screening and Characterization of Phytochemicals Using hydroethanolic Leaf Extract of Caesalpinia Pulcherrima","authors":"A. Ilangovan, Venkatesh Raghu, R. Venugopal, Narayan Vijay, Yellapa Yellasamy, Akshaya Venkatramanan","doi":"10.2174/2211550109999201026091132","DOIUrl":"https://doi.org/10.2174/2211550109999201026091132","url":null,"abstract":"\u0000\u0000 Novel Therapeutic Phytochemical studies are based on the use of plants\u0000in the production of drugs. The present study was carried out to perform the screening of phytochemicals\u0000and their quantitative analysis to assess in-vitro antioxidant activities of the hydroethanolic\u0000leaf extract of Caesalpinia Pulcherrima. FT-IR and GC-MS analyses of hydroethanolic leaf extract\u0000of Caesalpinia pulcherrima were also conducted.\u0000\u0000\u0000\u0000The investigation of qualitative and determination of quantitative phytochemical analysis\u0000were performed using standard procedures. The total alkaloid, flavonoid, phenols, and tannin\u0000content were determined spectrophotometrically. DPPH (2,2-Diphenyl-1-picrylhydrazyl) free radical\u0000scavenging activity and ABTS (2,2’-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)) free\u0000radical scavenging activity of hydroethanolic leaf extract of Caesalpinia pulcherrima were estimated\u0000by standard protocol. The identification of functional groups was made using plant leaf extracts\u0000by FTIR and GCMS.\u0000\u0000\u0000\u0000The hydroethanolic leaf extract of Caesalpinia Pulcherrima gives positive results for alkaloids,\u0000flavonoids, phenols, carbohydrates, tannins, amino acids, and proteins. The content of total\u0000alkaloids, flavonoids, phenols, and tannins varies from 8.4 AE/g, 3.3 CE/g, 2.9, and 3.2 GAE/g, respectively.\u0000The antioxidant assay and IC50 values were found to be DPPH (43.3μg/ml), ABTS\u0000(46.1 μg/ml), and ascorbic acid (41μg/ml), respectively and concentration ranging from 20 to 100\u0000μg/ml. Functional groups were also identified using the extract by FTIR and GCMS.\u0000\u0000\u0000\u0000From this work, it can be concluded that the presence of phyto-component makes the\u0000plant useful in the treatment of various diseases. As such, it has been found that the hydroethanolic\u0000leaf extract of the plant contains more components and is beneficial for further research.\u0000","PeriodicalId":10850,"journal":{"name":"Current Biotechnology","volume":"76 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77531272","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-10-26DOI: 10.2174/2211550109999201026091512
S. R. Toleti
The review is an attempt to introduce the readers in brief about biofilms and their implications as well as some new perceptions in biotechnology. Biofilms are adherent microbial communities, which are developed on submerged surfaces in aquatic environments. Biofilms play a significant role in exopolymer production, material deterioration and also cause harmful infections. Further, the role of corrosion causing biofilm bacteria in deterioration of different materials, microbial biofilms and their enzymatic processes in reducing the toxicity of pollutants in industrial effluents are elaborated, along with clean technologies for wastewater treatment. Biotechnology is defined as any technological application that uses biological systems to synthesize or modify products or processes. The applications include biochemical processes, medical care, cell and tissue culture, as well as synthetic biology and others. Synthetic biology details about the design, construction of new biological components and systems for useful purposes. Finally, to overcome the limitations that are inherent to the use of cellular host’s, cell-free systems as critical platforms for synthetic biology applications. This mini-review also mentions new diagnostic products based on enzymes, monoclonal antibodies and engineered proteins, as well as novel prophylactic vaccines.
{"title":"Microbial Biofilms and Biotechnology – Some Perceptions","authors":"S. R. Toleti","doi":"10.2174/2211550109999201026091512","DOIUrl":"https://doi.org/10.2174/2211550109999201026091512","url":null,"abstract":"\u0000\u0000The review is an attempt to introduce the readers in brief about biofilms and their implications\u0000as well as some new perceptions in biotechnology. Biofilms are adherent microbial communities,\u0000which are developed on submerged surfaces in aquatic environments. Biofilms play a significant\u0000role in exopolymer production, material deterioration and also cause harmful infections. Further,\u0000the role of corrosion causing biofilm bacteria in deterioration of different materials, microbial\u0000biofilms and their enzymatic processes in reducing the toxicity of pollutants in industrial effluents\u0000are elaborated, along with clean technologies for wastewater treatment. Biotechnology is defined\u0000as any technological application that uses biological systems to synthesize or modify products or\u0000processes. The applications include biochemical processes, medical care, cell and tissue culture, as\u0000well as synthetic biology and others. Synthetic biology details about the design, construction of\u0000new biological components and systems for useful purposes. Finally, to overcome the limitations\u0000that are inherent to the use of cellular host’s, cell-free systems as critical platforms for synthetic biology\u0000applications. This mini-review also mentions new diagnostic products based on enzymes,\u0000monoclonal antibodies and engineered proteins, as well as novel prophylactic vaccines.\u0000","PeriodicalId":10850,"journal":{"name":"Current Biotechnology","volume":"369 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77335652","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-10-26DOI: 10.2174/2211550109999201026085353
T. López-Goerne, Francisco J. Padilla-Godínez, Luis Pérez-Dávalos, Paola Ramírez-Olivares, D. Arellano
Diabetic foot ulcers (DFUs) exhibit 80% of prevalence in Mexico. Efficient tissue regeneration therapies are the key factors to avoid amputations. In this study, the healing properties of a Cu/TiO2-SiO2 nanobiocatalyst applied in DFUs were analyzed. Furthermore, the morphology and crystalline structures were characterized. The nanobiocatalyst was synthesized by a sol-gel patented method proposed by López et al. The compound was characterized by scanning and transmission electron microscopies and Xray diffraction. The nanoparticles were embedded in a polymeric gel matrix (nanogel), which was utilized as a conservative therapy for chronic non-healing DFU in 8 patients with several comorbidities and chronic complications of diabetes. Wound debridement was performed prior to the nanogel administration. The nanogel was applied over the ulcers on alternate days for different periods of time, depending on the case. Significant improvement in terms of enhanced epithelialization was observed in the wound healing process after a few applications. Infection spread was limited, and tissue regeneration was enhanced, with significant healing of the ulcers observed in each case. Furthermore, the successful outcome allowed to avoid the amputations that were proposed to some of the patients. The study proved the efficiency of the nanobiocatalyst as a safe, conservative therapy for chronic non-healing DFUs. Further investigation must be carried out to fully elucidate the wound-healing mechanisms of the nanoparticles.
{"title":"Nanobiocatalysts: Cu/TiO2-SiO2 Nanoparticles as Tissue-Regeneration Treatment for Diabetic Foot Ulcers: In Vivo Studies","authors":"T. López-Goerne, Francisco J. Padilla-Godínez, Luis Pérez-Dávalos, Paola Ramírez-Olivares, D. Arellano","doi":"10.2174/2211550109999201026085353","DOIUrl":"https://doi.org/10.2174/2211550109999201026085353","url":null,"abstract":"\u0000\u0000Diabetic foot ulcers (DFUs) exhibit 80% of prevalence in Mexico. Efficient\u0000tissue regeneration therapies are the key factors to avoid amputations.\u0000\u0000\u0000\u0000In this study, the healing properties of a Cu/TiO2-SiO2 nanobiocatalyst applied in DFUs\u0000were analyzed. Furthermore, the morphology and crystalline structures were characterized.\u0000\u0000\u0000\u0000The nanobiocatalyst was synthesized by a sol-gel patented method proposed by López et\u0000al. The compound was characterized by scanning and transmission electron microscopies and Xray\u0000diffraction. The nanoparticles were embedded in a polymeric gel matrix (nanogel), which was\u0000utilized as a conservative therapy for chronic non-healing DFU in 8 patients with several comorbidities\u0000and chronic complications of diabetes. Wound debridement was performed prior to the\u0000nanogel administration. The nanogel was applied over the ulcers on alternate days for different periods\u0000of time, depending on the case.\u0000\u0000\u0000\u0000Significant improvement in terms of enhanced epithelialization was observed in the\u0000wound healing process after a few applications. Infection spread was limited, and tissue regeneration\u0000was enhanced, with significant healing of the ulcers observed in each case. Furthermore, the\u0000successful outcome allowed to avoid the amputations that were proposed to some of the patients.\u0000\u0000\u0000\u0000The study proved the efficiency of the nanobiocatalyst as a safe, conservative therapy\u0000for chronic non-healing DFUs. Further investigation must be carried out to fully elucidate the\u0000wound-healing mechanisms of the nanoparticles.\u0000","PeriodicalId":10850,"journal":{"name":"Current Biotechnology","volume":"19 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75156853","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-10-21DOI: 10.2174/2211550109999201021165210
J. Frère, Olivier Verlaine
The study of the interactions between enzymes and inactivators can often be performed with the help of the reporter substrate method in which the time-dependent decrease of the rate of substrate disappearance (or product formation) is monitored. In the present contribution, we wish to describe examples of the utilization of this rapid and efficient method for reactions whose rates can be monitored by spectrophotometric or fluorimetric measurements. After the collection of the data in an Excel file, a very simple program can be applied to extract the values of pseudo-- first-order rate constants. The inactivation can be complete or result in a steady-state if the inactivated adduct is not totally stable or if the inactivation reaction is reversible. Similarly, the method can be used in the cases of so-called “slow binding” inhibitors. The same type of analysis allows the easy determination of kcat/Km values for substrates for which the Km value is rather low. We show that this very rapid method (less than 5 min) yields very good values of the desired kinetic parameter even if the total absorbance variations are very low (0.1 or less). In conclusion, the described experimental approach is particularly useful when applied to the reporter substrate method but it also allows the estimation of the kcat/Km parameter even if the Km value is rather low. The authors wish to dedicate this paper to the memory of the late Michel Rinné (1941-2009) whose contribution to making the data analysis program very user-friendly was invaluable.
{"title":"First-order Kinetics in the Study of Enzymes: Applications to the Reporter Substrate Method and to the Estimation of kcatKm","authors":"J. Frère, Olivier Verlaine","doi":"10.2174/2211550109999201021165210","DOIUrl":"https://doi.org/10.2174/2211550109999201021165210","url":null,"abstract":"\u0000\u0000The study of the interactions between enzymes and inactivators can often be performed\u0000with the help of the reporter substrate method in which the time-dependent decrease of the rate of\u0000substrate disappearance (or product formation) is monitored. In the present contribution, we wish\u0000to describe examples of the utilization of this rapid and efficient method for reactions whose rates\u0000can be monitored by spectrophotometric or fluorimetric measurements. After the collection of the\u0000data in an Excel file, a very simple program can be applied to extract the values of pseudo--\u0000first-order rate constants. The inactivation can be complete or result in a steady-state if the inactivated\u0000adduct is not totally stable or if the inactivation reaction is reversible. Similarly, the method can\u0000be used in the cases of so-called “slow binding” inhibitors. The same type of analysis allows the\u0000easy determination of kcat/Km values for substrates for which the Km value is rather low. We show\u0000that this very rapid method (less than 5 min) yields very good values of the desired kinetic parameter\u0000even if the total absorbance variations are very low (0.1 or less).\u0000\u0000\u0000\u0000In conclusion, the described experimental approach is particularly useful when applied to the reporter\u0000substrate method but it also allows the estimation of the kcat/Km parameter even if the Km value\u0000is rather low.\u0000\u0000\u0000\u0000The authors wish to dedicate this paper to the memory of the late Michel Rinné (1941-2009) whose\u0000contribution to making the data analysis program very user-friendly was invaluable.\u0000","PeriodicalId":10850,"journal":{"name":"Current Biotechnology","volume":"96 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83532215","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-09-08DOI: 10.2174/2211550109999200908090745
T. P. Krishna, Maharajan Theivanayagam, G. V. Roch, V. Duraipandiyan, S. Ignacimuthu
Finger millet is a superior staple food for human beings. Microsatellite or Simple Sequence Repeat (SSR) marker is a powerful tool for genetic mapping, diversity analysis and plant breeding. In finger millet, microsatellites show a higher level of polymorphism than other molecular marker systems. The identification and development of microsatellite markers are extremely expensive and time-consuming. Only less than 50% of SSR markers have been developed from microsatellite sequences for finger millet. Therefore, it is important to transfer SSR markers developed for related species/genus to finger millet. Cross-genome transferability is the easiest and cheapest method to develop SSR markers. Many comparative mapping studies using microsatellite markers clearly revealed the presence of synteny within the genomes of closely related species/ genus. Sufficient homology exists among several crop plant genomes in the sequences flanking the SSR loci. Thus, the SSR markers are beneficial to amplify the target regions in the finger millet genome. Many SSR markers were used for the analysis of cross-genome amplification in various plants such as Setaria italica, Pennisetum glaucum, Oryza sativa, Triticum aestivum, Zea mays and Hordeum vulgare. However, there is very little information available about cross-genome amplification of these markers in finger millet. The only limited report is available for the utilization of cross-genome amplified microsatellite markers in genetic analysis, gene mapping and other applications in finger millet. This review highlights the importance and implication of microsatellite markers such as genomic SSR (gSSR) and Expressed Sequence Tag (EST)-SSR in cross-genome analysis in finger millet. Nowadays, crop improvement has been one of the major priority areas of research in agriculture. The genome assisted breeding and genetic engineering plays a very crucial role in enhancing crop productivity. The rapid advance in molecular marker technology is helpful for crop improvement. Therefore, this review will be very helpful to the researchers for understanding the importance and implication of SSR markers in closely related species.
{"title":"Microsatellite Marker: Importance and Implications of Cross-genome Analysis for Finger Millet (Eleusine coracana (L.) Gaertn)","authors":"T. P. Krishna, Maharajan Theivanayagam, G. V. Roch, V. Duraipandiyan, S. Ignacimuthu","doi":"10.2174/2211550109999200908090745","DOIUrl":"https://doi.org/10.2174/2211550109999200908090745","url":null,"abstract":"\u0000\u0000Finger millet is a superior staple food for human beings. Microsatellite or Simple Sequence\u0000Repeat (SSR) marker is a powerful tool for genetic mapping, diversity analysis and plant\u0000breeding. In finger millet, microsatellites show a higher level of polymorphism than other molecular\u0000marker systems. The identification and development of microsatellite markers are extremely expensive\u0000and time-consuming. Only less than 50% of SSR markers have been developed from microsatellite\u0000sequences for finger millet. Therefore, it is important to transfer SSR markers developed\u0000for related species/genus to finger millet. Cross-genome transferability is the easiest and\u0000cheapest method to develop SSR markers. Many comparative mapping studies using microsatellite\u0000markers clearly revealed the presence of synteny within the genomes of closely related species/\u0000genus. Sufficient homology exists among several crop plant genomes in the sequences flanking the\u0000SSR loci. Thus, the SSR markers are beneficial to amplify the target regions in the finger millet\u0000genome. Many SSR markers were used for the analysis of cross-genome amplification in various\u0000plants such as Setaria italica, Pennisetum glaucum, Oryza sativa, Triticum aestivum, Zea mays and\u0000Hordeum vulgare. However, there is very little information available about cross-genome amplification\u0000of these markers in finger millet. The only limited report is available for the utilization of\u0000cross-genome amplified microsatellite markers in genetic analysis, gene mapping and other applications\u0000in finger millet. This review highlights the importance and implication of microsatellite markers\u0000such as genomic SSR (gSSR) and Expressed Sequence Tag (EST)-SSR in cross-genome analysis\u0000in finger millet. Nowadays, crop improvement has been one of the major priority areas of research\u0000in agriculture. The genome assisted breeding and genetic engineering plays a very crucial\u0000role in enhancing crop productivity. The rapid advance in molecular marker technology is helpful\u0000for crop improvement. Therefore, this review will be very helpful to the researchers for understanding\u0000the importance and implication of SSR markers in closely related species.\u0000","PeriodicalId":10850,"journal":{"name":"Current Biotechnology","volume":"9 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78899448","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-09-08DOI: 10.2174/2211550109999200908090053
F. Bettin, Letícia O. da Rosa, Q. Montanari, A. J. Dillon, M. M. da Silveira
Laccases are multi-copper enzymes that oxidize phenolic/aromatic compounds and represent a promising alternative to environmental decontamination processes and biotechnological applications. The effects of pH and temperature on the growth and the production of laccases during the cultivation of Pleurotus sajor-caju PS-2001 in stirred-tank bioreactor were assessed. Assays were performed at fixed pH values from 4.5 to 7.5 (28°C) and at temperatures from 24 to 36°C (pH 6.5). In pH testing, larger biomass concentration (4.5 g L-1) was reached at pH 5.5, whereas concentrations of 3.7, 3.1 and 1.7 g L-1 were measured at pH 4.5, 6.5 and 7.5, respectively. With ABTS as substrate, peaks of laccases activity of 50, 30 and 24 U mL-1, at pH 6.5, 5.5 and 7.5, respectively, were detected. Under different temperatures, higher mycelial concentrations (3.0 g L-1) were quantified at 66 hours at 28°C, while concentrations below 2.0 g L-1 were observed at 24, 32, and 36°C. Maximum laccases activities of 50, 42, 6 and 5 U mL-1 were obtained at 28, 32, 24, and 36°C, respectively. In all tests, the presence of other phenol oxidases – total peroxidase, manganese peroxidase, lignin peroxidase and veratryl alcohol oxidase – was observed. The results indicate that variations in pH and temperature during fungal cultivation strongly affect the enzymatic activity and growth kinetics of P. sajor-caju PS-2001 in a stirredtank bioreactor.
漆酶是一种多铜酶，可以氧化酚类/芳香族化合物，是一种有前途的环境净化过程和生物技术应用的替代品。研究了pH和温度对平菇PS-2001在搅拌槽生物反应器中生长和产漆酶的影响。测定在固定pH值为4.5至7.5(28°C)和24至36°C (pH 6.5)的条件下进行。在pH测试中，pH为5.5时生物量浓度最高(4.5 g L-1)，而pH为4.5、6.5和7.5时生物量浓度分别为3.7、3.1和1.7 g L-1。以ABTSas为底物，分别在pH 6.5、5.5和7.5条件下检测到50、30和24 U mL-1的漆酶活性峰值。在不同温度下，28℃条件下66 h菌丝浓度达到3.0 g L-1, 24、32、36℃条件下菌丝浓度低于2.0 g L-1。在28°、32°、24°和36°C时，漆酶的最大活性分别为50、42、6和5 U mL-1。在所有测试中，观察到其他酚氧化酶-总过氧化物酶，锰过氧化物酶，木质素过氧化物酶和戊曲醇氧化酶-的存在。结果表明，在搅拌式生物反应器中，真菌培养过程中pH和温度的变化强烈影响P. sajora -caju PS-2001的酶活性和生长动力学。
{"title":"Effect of pH and Temperature on the Growth and Laccases Production in the Cultivation of Pleurotus sajor-caju PS-2001 in Stirred-tank Bioreactor","authors":"F. Bettin, Letícia O. da Rosa, Q. Montanari, A. J. Dillon, M. M. da Silveira","doi":"10.2174/2211550109999200908090053","DOIUrl":"https://doi.org/10.2174/2211550109999200908090053","url":null,"abstract":"\u0000\u0000Laccases are multi-copper enzymes that oxidize phenolic/aromatic compounds\u0000and represent a promising alternative to environmental decontamination processes and\u0000biotechnological applications.\u0000\u0000\u0000\u0000The effects of pH and temperature on the growth and the production of laccases during\u0000the cultivation of Pleurotus sajor-caju PS-2001 in stirred-tank bioreactor were assessed.\u0000\u0000\u0000\u0000Assays were performed at fixed pH values from 4.5 to 7.5 (28°C) and at temperatures\u0000from 24 to 36°C (pH 6.5).\u0000\u0000\u0000\u0000In pH testing, larger biomass concentration (4.5 g L-1) was reached at pH 5.5, whereas concentrations\u0000of 3.7, 3.1 and 1.7 g L-1 were measured at pH 4.5, 6.5 and 7.5, respectively. With ABTS\u0000as substrate, peaks of laccases activity of 50, 30 and 24 U mL-1, at pH 6.5, 5.5 and 7.5, respectively,\u0000were detected. Under different temperatures, higher mycelial concentrations (3.0 g L-1) were\u0000quantified at 66 hours at 28°C, while concentrations below 2.0 g L-1 were observed at 24, 32, and\u000036°C. Maximum laccases activities of 50, 42, 6 and 5 U mL-1 were obtained at 28, 32, 24, and\u000036°C, respectively. In all tests, the presence of other phenol oxidases – total peroxidase, manganese\u0000peroxidase, lignin peroxidase and veratryl alcohol oxidase – was observed.\u0000\u0000\u0000\u0000The results indicate that variations in pH and temperature during fungal cultivation\u0000strongly affect the enzymatic activity and growth kinetics of P. sajor-caju PS-2001 in a stirredtank\u0000bioreactor.\u0000","PeriodicalId":10850,"journal":{"name":"Current Biotechnology","volume":"61 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74874960","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-08-02DOI: 10.2174/2211550109999200802154246
KumChol Ri, MyongRyong Ri, Yongchul Song, KyuHwan Kim, Chol Kim
The Klf6 gene, belonging to Krüppel-like family of C2H2 zinc finger transcription factors, is strongly associated with tumor formation through high somatic mutations in carcinomas of the prostate, liver, colon, stomach, lung, neck, pituitary gland and nervous system. Recently, Klf6 super-enhancer which strongly regulates Klf6 gene expression has been identified, and the function of Klf6 super-enhancer which regulates cell growth was studied. The development of inhibitors targeting BRD4-binding super-enhancers is a potential target therapeutic strategy for tumor therapy. However, the suppression of Klf6 super-enhancer function by BRD4 inhibitors is not known. CRISPR-Cas9 editing technique was used for the Klf6 super-enhancer deletion experiment, and the expression levels of several genes for cell clones were detected by qRT-PCR analysis and Western blotting. Cell proliferation assay was applied to evaluate the functional role of Klf6 super-enhancer using several BRD4 inhibitors. The interaction of several BRD4 inhibitors against the target protein was analyzed by molecular docking simulation. JQ-1, a human BRD4 inhibitor, inhibited Klf6 gene expression and its activity in HepG2 cells in a time and dose-dependent manner while simultaneously inhibiting cell growth. Besides, BETd-246, a human BRD4 inhibitor, strongly inhibited Klf6 gene expression, significantly inhibited cell growth, and exhibited higher efficacy than JQ-1. Molecular docking studies revealed that some key residues were critical for ligand-receptor interactions by forming hydrogen bonds with ligands (JQ-1: ASN140, BETd-246: ASN140, TYR106, LYS65, GLN58, MET105, and MET53). Our findings suggest that KLF6 is regulated by Klf6 super-enhancer and the targeting of Klf6 super-enhancer by BRD4 inhibitors may be an effective therapeutic strategy for liver cancer therapy.
{"title":"The Klf6 Super-enhancer Determines Klf6 Sensitivity to BRD4 Inhibitors in Human Hepatoma (HepG2) Cells","authors":"KumChol Ri, MyongRyong Ri, Yongchul Song, KyuHwan Kim, Chol Kim","doi":"10.2174/2211550109999200802154246","DOIUrl":"https://doi.org/10.2174/2211550109999200802154246","url":null,"abstract":"\u0000\u0000The Klf6 gene, belonging to Krüppel-like family of C2H2 zinc finger transcription\u0000factors, is strongly associated with tumor formation through high somatic mutations in\u0000carcinomas of the prostate, liver, colon, stomach, lung, neck, pituitary gland and nervous system.\u0000Recently, Klf6 super-enhancer which strongly regulates Klf6 gene expression has been identified,\u0000and the function of Klf6 super-enhancer which regulates cell growth was studied.\u0000\u0000\u0000\u0000The development of inhibitors targeting BRD4-binding super-enhancers is a potential\u0000target therapeutic strategy for tumor therapy. However, the suppression of Klf6 super-enhancer\u0000function by BRD4 inhibitors is not known.\u0000\u0000\u0000\u0000CRISPR-Cas9 editing technique was used for the Klf6 super-enhancer deletion experiment,\u0000and the expression levels of several genes for cell clones were detected by qRT-PCR analysis\u0000and Western blotting. Cell proliferation assay was applied to evaluate the functional role of\u0000Klf6 super-enhancer using several BRD4 inhibitors. The interaction of several BRD4 inhibitors\u0000against the target protein was analyzed by molecular docking simulation.\u0000\u0000\u0000\u0000JQ-1, a human BRD4 inhibitor, inhibited Klf6 gene expression and its activity in HepG2\u0000cells in a time and dose-dependent manner while simultaneously inhibiting cell growth. Besides,\u0000BETd-246, a human BRD4 inhibitor, strongly inhibited Klf6 gene expression, significantly inhibited\u0000cell growth, and exhibited higher efficacy than JQ-1. Molecular docking studies revealed that\u0000some key residues were critical for ligand-receptor interactions by forming hydrogen bonds with ligands\u0000(JQ-1: ASN140, BETd-246: ASN140, TYR106, LYS65, GLN58, MET105, and MET53).\u0000\u0000\u0000\u0000Our findings suggest that KLF6 is regulated by Klf6 super-enhancer and the targeting\u0000of Klf6 super-enhancer by BRD4 inhibitors may be an effective therapeutic strategy for liver cancer\u0000therapy.\u0000","PeriodicalId":10850,"journal":{"name":"Current Biotechnology","volume":"74 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73941135","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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