Rushyannah R. Killens-Cade, R. Turner, C. Macinnes, A. Grunden
Lipid-producing microalgae are emerging as the leading platform for producing alternative biofuels in response to diminishing petroleum reserves. Optimization of fatty acid production is required for efficient conversion of microalgal fatty acids into usable transportation fuels. Microbial lipases/esterases can be used to enhance fatty acid production because of their efficacy in catalyzing hydrolysis of esters into alcohols and fatty acids while minimizing the potential poisoning of catalysts needed in the biofuel production process. Although studies have extensively focused on lipases/esterases produced by mesophilic organisms, an understanding of lipases/esterases produced by thermophilic, acidic tolerant microbes, such as Metallosphaera sedula, is limited. In this work, the carboxylesterase from Metallosphaera sedula DSM5348 encoded by Msed_1072 was recombinantly expressed in Escherichia coli strain BL21 (λDE3). The purified enzyme either with a hexahistidine (His6)-tag (Msed_1072Nt and Msed_1072Ct) or without the hexahistidine (His6)-tag (Msed_1072) was biochemically characterized using a variety of substrates over a range of temperatures and pH and in the presence of metal ions, organic solvents, and detergents. In this study, the fusion of the protein with a hexahistidine (His6)-tag did not result in a change in substrate specificity, but the findings provide information on which enzyme variant can hydrolyze fatty acid esters in the presence of various chemicals, and this has important implication for their use in industrial processes. It also demonstrates that Metallosphaera sedula Msed_1072 can have application in microalgae-based biofuel production systems.
{"title":"Characterization of a Thermostable, Recombinant Carboxylesterase from the Hyperthermophilic Archaeon Metallosphaera sedula DSM5348","authors":"Rushyannah R. Killens-Cade, R. Turner, C. Macinnes, A. Grunden","doi":"10.4236/AER.2014.21001","DOIUrl":"https://doi.org/10.4236/AER.2014.21001","url":null,"abstract":"Lipid-producing microalgae are emerging as the leading platform for producing alternative biofuels in response to diminishing petroleum reserves. Optimization of fatty acid production is required for efficient conversion of microalgal fatty acids into usable transportation fuels. Microbial lipases/esterases can be used to enhance fatty acid production because of their efficacy in catalyzing hydrolysis of esters into alcohols and fatty acids while minimizing the potential poisoning of catalysts needed in the biofuel production process. Although studies have extensively focused on lipases/esterases produced by mesophilic organisms, an understanding of lipases/esterases produced by thermophilic, acidic tolerant microbes, such as Metallosphaera sedula, is limited. In this work, the carboxylesterase from Metallosphaera sedula DSM5348 encoded by Msed_1072 was recombinantly expressed in Escherichia coli strain BL21 (λDE3). The purified enzyme either with a hexahistidine (His6)-tag (Msed_1072Nt and Msed_1072Ct) or without the hexahistidine (His6)-tag (Msed_1072) was biochemically characterized using a variety of substrates over a range of temperatures and pH and in the presence of metal ions, organic solvents, and detergents. In this study, the fusion of the protein with a hexahistidine (His6)-tag did not result in a change in substrate specificity, but the findings provide information on which enzyme variant can hydrolyze fatty acid esters in the presence of various chemicals, and this has important implication for their use in industrial processes. It also demonstrates that Metallosphaera sedula Msed_1072 can have application in microalgae-based biofuel production systems.","PeriodicalId":65616,"journal":{"name":"酶研究进展(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70485025","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}
Phytase, also known as phytate-degrading enzyme, catalyzes the hydrolysis of phytate (inositol hexakisphosphate) with sequential release of phosphate and lower inositol phosphate. We report here a new plasmid construct designated as pMSuia from pBAD-TOPO that harbors a 1.1 kb phytase gene (phyMS) from Mycobacterium smegmatis, and expression as well as characterization of the purified recombinant M. smegmatis phytase. DNA sequencing analysis and multiple alignment exercise indicated that the M. smegmatis phytase is different from both known acid and alkaline phytases. The active ~45 kDa recombinant enzyme was expressed and confirmed by enzyme assay and Western blot analyses. Ni-NTA affinity purified recombinant M. smegmatis phytase exhibited specific activity of 233.51 U/mg, optimal pH of 3 and 7 and optimal temperature of 60°C. The purified enzyme retains almost 30% of the initial activity after incubation at 90°C for 60 min. The enzyme showed broad substrate specificity with Km and Vmax of the recombinant enzyme for sodium phytate substrate of 0.105 ± 0.016 mM and 26.93 ± 1.21 mM min-1, respectively.
植酸酶，又称植酸降解酶，催化水解植酸(六磷酸肌醇)，并依次释放磷酸和低磷酸肌醇。本文报道了从pBAD-TOPO中提取的含有耻毛分枝杆菌植酸酶基因(phyMS) 1.1 kb的pMSuia质粒，以及纯化的重组耻毛分枝杆菌植酸酶的表达和特性。DNA测序分析和多重比对表明，耻垢分枝杆菌植酸酶不同于已知的酸性和碱性植酸酶。表达了活性~ 45kda的重组酶，并通过酶分析和Western blot分析证实了重组酶的活性。Ni-NTA亲和纯化的重组臭茅植酸酶比活性为233.51 U/mg，最适pH为3和7，最适温度为60℃。在90°C下孵育60分钟后，纯化酶保持了近30%的初始活性。该酶对植酸钠底物的Km和Vmax分别为0.105±0.016 mM和26.93±1.21 mM min-1，具有广泛的底物特异性。
{"title":"Cloning and Expression of a Novel Phytase Gene (phyMS) from Mycobacterium smegmatis","authors":"Tamrin Nuge, Y. Hashim, A. Farouk, H. Salleh","doi":"10.4236/AER.2014.21003","DOIUrl":"https://doi.org/10.4236/AER.2014.21003","url":null,"abstract":"Phytase, also known as phytate-degrading enzyme, catalyzes the hydrolysis of phytate (inositol hexakisphosphate) with sequential release of phosphate and lower inositol phosphate. We report here a new plasmid construct designated as pMSuia from pBAD-TOPO that harbors a 1.1 kb phytase gene (phyMS) from Mycobacterium smegmatis, and expression as well as characterization of the purified recombinant M. smegmatis phytase. DNA sequencing analysis and multiple alignment exercise indicated that the M. smegmatis phytase is different from both known acid and alkaline phytases. The active ~45 kDa recombinant enzyme was expressed and confirmed by enzyme assay and Western blot analyses. Ni-NTA affinity purified recombinant M. smegmatis phytase exhibited specific activity of 233.51 U/mg, optimal pH of 3 and 7 and optimal temperature of 60°C. The purified enzyme retains almost 30% of the initial activity after incubation at 90°C for 60 min. The enzyme showed broad substrate specificity with Km and Vmax of the recombinant enzyme for sodium phytate substrate of 0.105 ± 0.016 mM and 26.93 ± 1.21 mM min-1, respectively.","PeriodicalId":65616,"journal":{"name":"酶研究进展(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70485074","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}
Nanami Hara, Shintaro Morisada, K. Ohto, H. Kawakita
High concentration of polymer solution in cosmetics has the essential role in keeping water on peel of skin. This study includes the papain activity in the high concentrated dextran solution for keratin hydrolysis. Papain is the industrial and a representative hydrolase. The concentration of dextran was ranged to 100 g/L. In the increasing concentration of dextran, the activity of papain decreased due to the low diffusivity of papain and substrate. Even in concentrated dextran solution, keratin powder was possible to be hydrolyzed at the high efficiency.
{"title":"Papain Activity in Dextran Solution for Keratin Hydrolysis","authors":"Nanami Hara, Shintaro Morisada, K. Ohto, H. Kawakita","doi":"10.4236/AER.2014.21005","DOIUrl":"https://doi.org/10.4236/AER.2014.21005","url":null,"abstract":"High concentration of polymer solution in cosmetics has the essential role in keeping water on peel of skin. This study includes the papain activity in the high concentrated dextran solution for keratin hydrolysis. Papain is the industrial and a representative hydrolase. The concentration of dextran was ranged to 100 g/L. In the increasing concentration of dextran, the activity of papain decreased due to the low diffusivity of papain and substrate. Even in concentrated dextran solution, keratin powder was possible to be hydrolyzed at the high efficiency.","PeriodicalId":65616,"journal":{"name":"酶研究进展(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70485486","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}
Enzyme kinetic parameters have been estimated using MATLAB software via the Wilkinson non-linear regression technique. The MATLAB script file written to implement this technique is short and very straightforward. Several software tools are commercially available for this purpose, with many graphical user interface (GUI) features. A routine use of these packages might offer immediate satisfaction of interactive hands-on experience; but in some cases the researcher might wish to write his/her own code and compare the results for further confirmation. Today MATLAB is in use in almost all the schools and laboratories as a standard software tool. So this paper is aimed at helping enzyme researchers to make use of this powerful software for estimation of parameters. It enables the incorporation of the analytical steps behind parameter estimation in an easy-to-follow manner and furnishes better visualization.
{"title":"Parameter Estimation in Different Enzyme Reactions","authors":"S. Nelatury, C. Nelatury, Mary Vagula","doi":"10.4236/AER.2014.21002","DOIUrl":"https://doi.org/10.4236/AER.2014.21002","url":null,"abstract":"Enzyme kinetic parameters have been estimated using MATLAB software via the Wilkinson non-linear regression technique. The MATLAB script file written to implement this technique is short and very straightforward. Several software tools are commercially available for this purpose, with many graphical user interface (GUI) features. A routine use of these packages might offer immediate satisfaction of interactive hands-on experience; but in some cases the researcher might wish to write his/her own code and compare the results for further confirmation. Today MATLAB is in use in almost all the schools and laboratories as a standard software tool. So this paper is aimed at helping enzyme researchers to make use of this powerful software for estimation of parameters. It enables the incorporation of the analytical steps behind parameter estimation in an easy-to-follow manner and furnishes better visualization.","PeriodicalId":65616,"journal":{"name":"酶研究进展(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70485037","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}
M. Vella, T. Hunter, C. Farrugia, A. Pearson, G. Hunter
Xanthine oxidoreductase (XOR) is a molybdoflavoprotein mainly involved in purine catabolism. It exists in two forms, the oxidase (XO) and dehydrogenase (XDH) which are inter-convertible within mammalian cells. Although various researchers have reported the extraction of mammalian XOR, no extractions have yet been carried out in Malta and subsequently no characterizations are available. In this study, XOR was successfully purified from bovine, caprine and ovine milk through a multistep purification process involving both chemical and chromatographic techniques. The molecular weights of the native enzyme were found to be 295 kDa, 281 kDa and 275 kDa, representing the bovine, caprine and ovine XOR respectively. Western blot showed XOR to be represented on SDS-PAGE by a minimum of three major bands having molecular weights of 151 kDa, 131 kDa and 85 kDa. While all samples showed activity on native PAGE, spectrophotometric assays revealed the bovine XOR to be the most active. Surprisingly, the addition of NAD+ to the assay mixture inhibited enzyme activity of the bovine and caprine XOR whereas the ovine XOR doubled its activity in response to NAD+. The latter also showed a lower binding affinity to heparin. Following incubation with trypsin, XOR was irreversibly converted to its oxidase form in all samples as reflected by the observed increase in XO activity.
{"title":"Purification and Characterisation of Xanthine Oxidoreductases from Local Bovids in Malta","authors":"M. Vella, T. Hunter, C. Farrugia, A. Pearson, G. Hunter","doi":"10.4236/AER.2014.21006","DOIUrl":"https://doi.org/10.4236/AER.2014.21006","url":null,"abstract":"Xanthine oxidoreductase (XOR) is a molybdoflavoprotein mainly involved in purine catabolism. It exists in two forms, the oxidase (XO) and dehydrogenase (XDH) which are inter-convertible within mammalian cells. Although various researchers have reported the extraction of mammalian XOR, no extractions have yet been carried out in Malta and subsequently no characterizations are available. In this study, XOR was successfully purified from bovine, caprine and ovine milk through a multistep purification process involving both chemical and chromatographic techniques. The molecular weights of the native enzyme were found to be 295 kDa, 281 kDa and 275 kDa, representing the bovine, caprine and ovine XOR respectively. Western blot showed XOR to be represented on SDS-PAGE by a minimum of three major bands having molecular weights of 151 kDa, 131 kDa and 85 kDa. While all samples showed activity on native PAGE, spectrophotometric assays revealed the bovine XOR to be the most active. Surprisingly, the addition of NAD+ to the assay mixture inhibited enzyme activity of the bovine and caprine XOR whereas the ovine XOR doubled its activity in response to NAD+. The latter also showed a lower binding affinity to heparin. Following incubation with trypsin, XOR was irreversibly converted to its oxidase form in all samples as reflected by the observed increase in XO activity.","PeriodicalId":65616,"journal":{"name":"酶研究进展(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70485499","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}
Cassandra M. Larimer, Dejan Slavnic, L. Pitstick, Jacalyn M. Green
Reduced folic acid derivatives support biosynthesis of DNA, RNA and amino acids in bacteria as well as in eukaryotes, including humans. While the genes and steps for bacterial folic acid synthesis are known, those associated with folic acid catabolism are not well understood. A folate catabolite found in both humans and bacteria is p-aminobenzoyl-glutamate (PABA-GLU). The enzyme p-aminobenzoyl-glutamate hydrolase (PGH) breaks down PABA-GLU and is part of an apparent operon, the abg region, in E. coli. The subunits of PGH possess sequence and catalytic similarities to carboxypeptidase enzymes from Pseudomonas species. A comparison of the subunit sequences and activity of PGH, relative to carboxypeptidase enzymes, may lead to a better understanding of bacterial physiology and pathway evolution. We first compared the amino acid sequences of AbgA, AbgB and carboxypeptidase G2 from Pseudomonas sp. RS-16, which has been crystallized. Then we compared the enzyme activities of E. coli PGH and commercially available Pseudomonas carboxypeptidase G using spectrophotometric assays measuring cleavage of PABA-GLU, folate, aminopterin, methotrexate, 5-formyltetrahydrofolate, and 5-methyltetrahydrofolate. The Km and Vmax values for the folate and anti-folate substrates of PGH could not be determined, because the instrument reached its limit before the enzyme was saturated. Therefore, activity of PGH was compared to the activity of CPG, or normalized to PABA-GLU (nmole/min/µg). Relative to its activity with 10 µM PABA-GLU (100%), PGH cleaved glutamate from methotrexate (48%), aminopterin (45%) and folate (9%). Reduced folates leucovorin (5-formyltetrahydrofolate) and 5-methyltetrahydrofolate were not cleaved by PGH. Our data suggest that E. coli PGH is specific for PABA-GLU as its activity with natural folates (folate, 5-methyltetrahydrofolate, and leucovorin) was very poor. It does, however, have some ability to cleave anti-folates which may have clinical applications in treatment of chemotherapy overdose.
{"title":"Comparison of Substrate Specificity of Escherichia Coli p-Aminobenzoyl-Glutamate Hydrolase with Pseudomonas Carboxypeptidase G","authors":"Cassandra M. Larimer, Dejan Slavnic, L. Pitstick, Jacalyn M. Green","doi":"10.4236/aer.2014.21004","DOIUrl":"https://doi.org/10.4236/aer.2014.21004","url":null,"abstract":"Reduced folic acid derivatives support biosynthesis of DNA, RNA and amino acids in bacteria as well as in eukaryotes, including humans. While the genes and steps for bacterial folic acid synthesis are known, those associated with folic acid catabolism are not well understood. A folate catabolite found in both humans and bacteria is p-aminobenzoyl-glutamate (PABA-GLU). The enzyme p-aminobenzoyl-glutamate hydrolase (PGH) breaks down PABA-GLU and is part of an apparent operon, the abg region, in E. coli. The subunits of PGH possess sequence and catalytic similarities to carboxypeptidase enzymes from Pseudomonas species. A comparison of the subunit sequences and activity of PGH, relative to carboxypeptidase enzymes, may lead to a better understanding of bacterial physiology and pathway evolution. We first compared the amino acid sequences of AbgA, AbgB and carboxypeptidase G2 from Pseudomonas sp. RS-16, which has been crystallized. Then we compared the enzyme activities of E. coli PGH and commercially available Pseudomonas carboxypeptidase G using spectrophotometric assays measuring cleavage of PABA-GLU, folate, aminopterin, methotrexate, 5-formyltetrahydrofolate, and 5-methyltetrahydrofolate. The Km and Vmax values for the folate and anti-folate substrates of PGH could not be determined, because the instrument reached its limit before the enzyme was saturated. Therefore, activity of PGH was compared to the activity of CPG, or normalized to PABA-GLU (nmole/min/µg). Relative to its activity with 10 µM PABA-GLU (100%), PGH cleaved glutamate from methotrexate (48%), aminopterin (45%) and folate (9%). Reduced folates leucovorin (5-formyltetrahydrofolate) and 5-methyltetrahydrofolate were not cleaved by PGH. Our data suggest that E. coli PGH is specific for PABA-GLU as its activity with natural folates (folate, 5-methyltetrahydrofolate, and leucovorin) was very poor. It does, however, have some ability to cleave anti-folates which may have clinical applications in treatment of chemotherapy overdose.","PeriodicalId":65616,"journal":{"name":"酶研究进展(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70485478","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}
Intracellular iron levels and the expression of superoxide dismutase (SOD) and hydroperoxidase (HP) are regulated in Gram-negative bacteria by the iron(II)-activated ferric uptake regula- tor (Fur). We have previously observed that the expression of SOD in exponential phase Escherichia coli is dependent upon the redox state of iron in media, consistent with the ferrous specificity of Fur regulation (Bertrand et al., Med. Hypotheses 78: 130 - 133, 2012). Through the non-denaturing electrophoretic technique we have determined the Escherichia coli expression profiles of SOD and HP in response to iron challenge throughout lag, logarithmic, and stationary phases of replication. Lag phase SOD presented an unusual expression profile such that SOD expression was unresponsive to iron challenge, analogous to observations of mutant strains lacking Fur and of E. coli incubated in iron-deplete media. Challenging Escherichia coli with iron during logarithmic phase revealed that length of exposure to oxidants is unlikely to be the cause of SOD unresponsiveness in lag phase. HP activity was up-regulated two- or three-fold throughout all growth phases in response to iron challenge, but did not present redox- or growth phase-specific outcomes in a manner analogous to SOD. We hypothesize that low Fur levels during lag phase are responsible for unresponsive SOD.
革兰氏阴性菌胞内铁水平和超氧化物歧化酶(SOD)和氢过氧化物酶(HP)的表达受铁(II)激活的铁摄取调节因子(Fur)的调控。我们之前观察到，指数期大肠杆菌中SOD的表达依赖于培养基中铁的氧化还原状态，这与Fur调节的铁特异性一致(Bertrand et al.， Med. hypothesis 78: 130 - 133, 2012)。通过非变性电泳技术，我们确定了大肠杆菌在复制的滞后期、对数期和固定期对铁挑战的反应中SOD和HP的表达谱。迟滞期SOD表现出不寻常的表达谱，使得SOD的表达对铁的挑战没有反应，类似于缺乏Fur的突变株和在缺铁培养基中培养的大肠杆菌的观察结果。在对数期用铁挑战大肠杆菌表明，暴露于氧化剂的时间不太可能是迟滞期SOD无反应性的原因。在铁胁迫下，HP活性在所有生长阶段均上调两到三倍，但不表现出与SOD类似的氧化还原或生长阶段特异性结果。我们假设迟滞期的低皮毛水平是导致SOD无反应的原因。
{"title":"Escherichia coli superoxide dismutase expression does not change in response to iron challenge during lag phase: Is the ferric uptake regulator to blame?","authors":"R. Bertrand, M. Eze","doi":"10.4236/AER.2013.14014","DOIUrl":"https://doi.org/10.4236/AER.2013.14014","url":null,"abstract":"Intracellular iron levels and the expression of superoxide dismutase (SOD) and hydroperoxidase (HP) are regulated in Gram-negative bacteria by the iron(II)-activated ferric uptake regula- tor (Fur). We have previously observed that the expression of SOD in exponential phase Escherichia coli is dependent upon the redox state of iron in media, consistent with the ferrous specificity of Fur regulation (Bertrand et al., Med. Hypotheses 78: 130 - 133, 2012). Through the non-denaturing electrophoretic technique we have determined the Escherichia coli expression profiles of SOD and HP in response to iron challenge throughout lag, logarithmic, and stationary phases of replication. Lag phase SOD presented an unusual expression profile such that SOD expression was unresponsive to iron challenge, analogous to observations of mutant strains lacking Fur and of E. coli incubated in iron-deplete media. Challenging Escherichia coli with iron during logarithmic phase revealed that length of exposure to oxidants is unlikely to be the cause of SOD unresponsiveness in lag phase. HP activity was up-regulated two- or three-fold throughout all growth phases in response to iron challenge, but did not present redox- or growth phase-specific outcomes in a manner analogous to SOD. We hypothesize that low Fur levels during lag phase are responsible for unresponsive SOD.","PeriodicalId":65616,"journal":{"name":"酶研究进展(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70484986","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}
Production of alkaline protease from Bacillus subtilis SHS-04 was investigated under different fermentation conditions involving low-cost substrates with the aim of optimizing yield of enzyme. Maximum enzyme production (1616.21 U/mL) was achieved using groundnut meal (0.75%) as nitrogen source and 0.5% glucose as carbon source at 48 h cultivation period, pH 9, 45 ° C and 200 rpm. The yield was 348% increase over comparable control samples. The alkaline protease had optimum temperature of 60 ° C and remarkably exhibited 80% relative activity at 70 ° C. It was highly thermostable showing 98.7% residual activity at 60 ° C after 60 minutes of incubation at pH 9.0 and was stable in the presence of organic solvents studied. These properties indicate the viability of the protease for biotechnological and industrial applications. The optimized yield of enzyme achieved in this study establishes groundnut meal as potential low-cost substrate for alkaline protease production by B. subtilis SHS-04.
{"title":"Optimized production and properties of thermostable alkaline protease from Bacillus subtilis SHS-04 grown on groundnut (Arachis hypogaea) meal","authors":"F. M. Olajuyigbe","doi":"10.4236/AER.2013.14012","DOIUrl":"https://doi.org/10.4236/AER.2013.14012","url":null,"abstract":"Production of alkaline protease from Bacillus subtilis SHS-04 was investigated under different fermentation conditions involving low-cost substrates with the aim of optimizing yield of enzyme. Maximum enzyme production (1616.21 U/mL) was achieved using groundnut meal (0.75%) as nitrogen source and 0.5% glucose as carbon source at 48 h cultivation period, pH 9, 45 ° C and 200 rpm. The yield was 348% increase over comparable control samples. The alkaline protease had optimum temperature of 60 ° C and remarkably exhibited 80% relative activity at 70 ° C. It was highly thermostable showing 98.7% residual activity at 60 ° C after 60 minutes of incubation at pH 9.0 and was stable in the presence of organic solvents studied. These properties indicate the viability of the protease for biotechnological and industrial applications. The optimized yield of enzyme achieved in this study establishes groundnut meal as potential low-cost substrate for alkaline protease production by B. subtilis SHS-04.","PeriodicalId":65616,"journal":{"name":"酶研究进展(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70484962","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}
Anita Williams, Ami Abbott, Jessica Chadwick, Alicia N. Thomas, Nathalia Cruz, A. Deng, Leah Ordinanza, John Tat, P. Russell
Previous studies showed that rabbit muscle phosphofructokinase-1 (PFK-1) activity losses due to dilution, due to inhibition by ascorbate, and due to some lithium salts were prevented by rabbit muscle aldolase. Chicken PFK-1 and fish PFK-1 interacted with ascorbate and were inhibited, consistent with a previously proposed function that ascorbate facilitates glycogen in resting muscle by inhibiting glycolysis. This report shows that a plant enzyme, spinach aldolase, has the same ability to prevent rabbit muscle PFK-1 activity loses as rabbit muscle aldolase and in some instances it was a better protector from activity losses than rabbit aldolase. Spinach aldolase also protected chicken and fish PFK-1s from inhibitions by ascorbate and from activity losses due to dilution. Prevention of losses PFK-1 activities from animal species by a plant protein, spinach aldolase, suggests an evolutionary conservative relationship between PFK-1s and aldolases.
{"title":"Spinach aldolase interactions with rabbit, chicken, and fish muscle phosphofructokinase-1","authors":"Anita Williams, Ami Abbott, Jessica Chadwick, Alicia N. Thomas, Nathalia Cruz, A. Deng, Leah Ordinanza, John Tat, P. Russell","doi":"10.4236/AER.2013.14013","DOIUrl":"https://doi.org/10.4236/AER.2013.14013","url":null,"abstract":"Previous studies showed that rabbit muscle phosphofructokinase-1 (PFK-1) activity losses due to dilution, due to inhibition by ascorbate, and due to some lithium salts were prevented by rabbit muscle aldolase. Chicken PFK-1 and fish PFK-1 interacted with ascorbate and were inhibited, consistent with a previously proposed function that ascorbate facilitates glycogen in resting muscle by inhibiting glycolysis. This report shows that a plant enzyme, spinach aldolase, has the same ability to prevent rabbit muscle PFK-1 activity loses as rabbit muscle aldolase and in some instances it was a better protector from activity losses than rabbit aldolase. Spinach aldolase also protected chicken and fish PFK-1s from inhibitions by ascorbate and from activity losses due to dilution. Prevention of losses PFK-1 activities from animal species by a plant protein, spinach aldolase, suggests an evolutionary conservative relationship between PFK-1s and aldolases.","PeriodicalId":65616,"journal":{"name":"酶研究进展(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70484974","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}
A. L. Ferrarezi, D. Pivetta, G. O. Bonilla-Rodriguez, R. Silva, J. Guisán, E. Gomes, B. Pessela
Lipases have important applications in biotechnological processes, motivating us to produce, purify, immobilize and perform a biochemical characterization of the lipase from Rhizomucor pusillus. The fungus was cultivated by solid state fermentation producing lipolytic activity of about 0.5 U/mL(4U/g). A partial purification by gel filtration chromatography in Se-phacryl S-100 allowed obtaining a yield of about 85% and a purification factor of 5.7. Our results revealed that the purified enzyme is very stable with some significant differences in its properties when compared to crude extract. The crude enzyme extract has an optimum pH and temperature of 7.5 ° C and 40 ° C, respectively. After purification, a shift of the optimum pH from 7 to 8 was observed, as well as a rise in optimumtemperature to 60 ° C and an increase in stability. The enzyme was immobilized on CNBr-Agarose and Octyl-Agarose supports, having the highest immobilization yield of 94% in the second resin. The major advantage of immobilization in hydrophobic media such as Octyl is in its hyper activation, which in this case was over 200%, a very interesting finding. Another advantage of this type of immobilization is the possibility of using the derivatives in biotechnological applications, such as in oil enriched with omega-3 as the results obtained in this study display the hydrolysis of 40% EPA and 7% DHA from sardine oil, promising results compared to the literature.
{"title":"Partial purification, immobilization and preliminary biochemical characterization of lipases from Rhizomucor pusillus","authors":"A. L. Ferrarezi, D. Pivetta, G. O. Bonilla-Rodriguez, R. Silva, J. Guisán, E. Gomes, B. Pessela","doi":"10.4236/AER.2013.14009","DOIUrl":"https://doi.org/10.4236/AER.2013.14009","url":null,"abstract":"Lipases have important applications in biotechnological processes, motivating us to produce, purify, immobilize and perform a biochemical characterization of the lipase from Rhizomucor pusillus. The fungus was cultivated by solid state fermentation producing lipolytic activity of about 0.5 U/mL(4U/g). A partial purification by gel filtration chromatography in Se-phacryl S-100 allowed obtaining a yield of about 85% and a purification factor of 5.7. Our results revealed that the purified enzyme is very stable with some significant differences in its properties when compared to crude extract. The crude enzyme extract has an optimum pH and temperature of 7.5 ° C and 40 ° C, respectively. After purification, a shift of the optimum pH from 7 to 8 was observed, as well as a rise in optimumtemperature to 60 ° C and an increase in stability. The enzyme was immobilized on CNBr-Agarose and Octyl-Agarose supports, having the highest immobilization yield of 94% in the second resin. The major advantage of immobilization in hydrophobic media such as Octyl is in its hyper activation, which in this case was over 200%, a very interesting finding. Another advantage of this type of immobilization is the possibility of using the derivatives in biotechnological applications, such as in oil enriched with omega-3 as the results obtained in this study display the hydrolysis of 40% EPA and 7% DHA from sardine oil, promising results compared to the literature.","PeriodicalId":65616,"journal":{"name":"酶研究进展(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70484686","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：