M. Fardilha, J. Figueiredo, M. Espona-Fiedler, Juliana Felgueiras, L. Korrodi-Gregório, S. Esteves, S. Rebelo, O. D. C. E. Silva, E. F. C. E. Silva, R. Pérez-Tomás
Reversible protein phosphorylation is a central regulatory mechanism of cell function. Deregulation of the balanced actions of protein kinases and phosphatases has been frequently associated with several pathological conditions, including cancer. Many studies have already addressed the role of protein kinases misregulation in cancer. However, much less is known about protein phosphatases influence. Phosphoprotein Phosphatase 1 (PPP1) is one of the major serine/threonine protein phosphatases who has three catalytic isoforms: PPP1CA, PPP1CB, and PPP1CC. Its function is achieved by binding to regulatory subunits, known as PPP1-interacting proteins (PIPs), which may prefer a catalytic isoform. Also, some inhibitors/enhancers may exhibit isoform specificity. Here we show that, prodigiosin (PG), a molecule with anticancer properties, promotes the formation of PPP1CA-AKT complex and not of PPP1CC-MAPK complex. Both, AKT and MAPK, are well-known PIPs from two pathways that crosstalk and regulate melanoma cells survival. In addition, the analysis performed using surface plasmon resonance (SPR) technology indicates that PPP1 interacts with obatoclax (OBX), a drug that belongs to the same family of PG. Overall, these results suggest that PG might, at least in part, act through PPP1C/PIPs. Also, this study is pioneer in demonstrating PPP1 isoform-specific modulation by small molecules.
{"title":"Phosphoprotein Phosphatase 1 Isoforms Alpha and Gamma Respond Differently to Prodigiosin Treatment and Present Alternative Kinase Targets in Melanoma Cells","authors":"M. Fardilha, J. Figueiredo, M. Espona-Fiedler, Juliana Felgueiras, L. Korrodi-Gregório, S. Esteves, S. Rebelo, O. D. C. E. Silva, E. F. C. E. Silva, R. Pérez-Tomás","doi":"10.4236/JBPC.2014.52008","DOIUrl":"https://doi.org/10.4236/JBPC.2014.52008","url":null,"abstract":"Reversible protein phosphorylation is a central regulatory mechanism of cell function. Deregulation of the balanced actions of protein kinases and phosphatases has been frequently associated with several pathological conditions, including cancer. Many studies have already addressed the role of protein kinases misregulation in cancer. However, much less is known about protein phosphatases influence. Phosphoprotein Phosphatase 1 (PPP1) is one of the major serine/threonine protein phosphatases who has three catalytic isoforms: PPP1CA, PPP1CB, and PPP1CC. Its function is achieved by binding to regulatory subunits, known as PPP1-interacting proteins (PIPs), which may prefer a catalytic isoform. Also, some inhibitors/enhancers may exhibit isoform specificity. Here we show that, prodigiosin (PG), a molecule with anticancer properties, promotes the formation of PPP1CA-AKT complex and not of PPP1CC-MAPK complex. Both, AKT and MAPK, are well-known PIPs from two pathways that crosstalk and regulate melanoma cells survival. In addition, the analysis performed using surface plasmon resonance (SPR) technology indicates that PPP1 interacts with obatoclax (OBX), a drug that belongs to the same family of PG. Overall, these results suggest that PG might, at least in part, act through PPP1C/PIPs. Also, this study is pioneer in demonstrating PPP1 isoform-specific modulation by small molecules.","PeriodicalId":62927,"journal":{"name":"生物物理化学(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70902557","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}
Ana Paula Caires dos Santos, M. S. Vieira, D. Deus, Rogério Jorge B. de Oliveira, A. Morikawa, Roque Aras Júnior, A. Atta, F. D. Couto, R. Maranhão, R. Couto
Dyslipidemia may influence enzymes and transfer proteins needed to the lipoprotein particle remodeling. Calculated indices and evaluation of lipoprotein particle size have widely been used to predict cardiovascular risk. The aim of this study was to evaluate HDL particle size and LDL particle size estimate based on TG/HDL-C as well as apoB/apoA-I ratio as possible marker and atherogenic indices, respectively, of cardiovascular disease risk in the presence of dyslipidemia. We evaluated 100 individuals of both gender, without treatment with lipid-lowering drugs, 27 normolipidemic and 73 dyslipidemic, such as isolated hypercholesterolemia (n = 16), isolated hypertriglyceridemia (n = 17), low HDL-C (n = 26) and mixed dyslipidemia (n = 14). The HDL particle size did not differ between groups. The TG/HDL-C ratio was higher in groups with isolated hypertriglyceridemia (4.2 ± 1.5), low HDL-C (5.2 ± 3.1) and mixed dyslipidemia (5.3 ± 1.6). The apoB/apoA-I ratio was increased in all groups of dyslipidemia (apoB/apoA-I > 0.5) when compared to normolipidemic (apoB/apoA-I = 0.5, p
{"title":"Atherogenic Indices and HDL Particle Size as Laboratory Parameters to Evaluate Cardiovascular Risk in the Presence of Dyslipidemia","authors":"Ana Paula Caires dos Santos, M. S. Vieira, D. Deus, Rogério Jorge B. de Oliveira, A. Morikawa, Roque Aras Júnior, A. Atta, F. D. Couto, R. Maranhão, R. Couto","doi":"10.4236/JBPC.2014.52004","DOIUrl":"https://doi.org/10.4236/JBPC.2014.52004","url":null,"abstract":"Dyslipidemia may influence enzymes and transfer proteins needed to the lipoprotein particle remodeling. Calculated indices and evaluation of lipoprotein particle size have widely been used to predict cardiovascular risk. The aim of this study was to evaluate HDL particle size and LDL particle size estimate based on TG/HDL-C as well as apoB/apoA-I ratio as possible marker and atherogenic indices, respectively, of cardiovascular disease risk in the presence of dyslipidemia. We evaluated 100 individuals of both gender, without treatment with lipid-lowering drugs, 27 normolipidemic and 73 dyslipidemic, such as isolated hypercholesterolemia (n = 16), isolated hypertriglyceridemia (n = 17), low HDL-C (n = 26) and mixed dyslipidemia (n = 14). The HDL particle size did not differ between groups. The TG/HDL-C ratio was higher in groups with isolated hypertriglyceridemia (4.2 ± 1.5), low HDL-C (5.2 ± 3.1) and mixed dyslipidemia (5.3 ± 1.6). The apoB/apoA-I ratio was increased in all groups of dyslipidemia (apoB/apoA-I > 0.5) when compared to normolipidemic (apoB/apoA-I = 0.5, p","PeriodicalId":62927,"journal":{"name":"生物物理化学(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70902715","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}
Mazur Iuliia, Kosterin Sergiy, V. Tetyana, Shkrabak Oleksandr
It has been theoretically predicted that under conditions leading to Gibbs-Donnan equilibrium in case when size of one compartment is very different from another (as in system “membrane vesicle/liposomes—incubation medium”) stable transmembrane potential can be formed, which value is sufficient to fit requirement of real transmembrane potential. Four partial cases were considered with different location and charge of impermeable ion and it was concluded that locations of impermeable ions in medium provide stable transmembrane potential with sufficient value of 60 - 70 mV. Potential-sensitive probe, such as DiOC6(3) and oxonol VI, were used to confirm the calculated potential. According to the change in fluorescence level and emission/excitation shift, a stable and relatively high transmembrane potential can be formed if salt of impermeable ion is located in incubation medium. Impermeable cations and anions may be used to create positive and negative transmembrane potential respectively.
{"title":"Gibbs-Donnan Potential as a Tool for Membrane Vesicles Polarization","authors":"Mazur Iuliia, Kosterin Sergiy, V. Tetyana, Shkrabak Oleksandr","doi":"10.4236/JBPC.2014.52009","DOIUrl":"https://doi.org/10.4236/JBPC.2014.52009","url":null,"abstract":"It has been theoretically predicted that under conditions leading to Gibbs-Donnan equilibrium in case when size of one compartment is very different from another (as in system “membrane vesicle/liposomes—incubation medium”) stable transmembrane potential can be formed, which value is sufficient to fit requirement of real transmembrane potential. Four partial cases were considered with different location and charge of impermeable ion and it was concluded that locations of impermeable ions in medium provide stable transmembrane potential with sufficient value of 60 - 70 mV. Potential-sensitive probe, such as DiOC6(3) and oxonol VI, were used to confirm the calculated potential. According to the change in fluorescence level and emission/excitation shift, a stable and relatively high transmembrane potential can be formed if salt of impermeable ion is located in incubation medium. Impermeable cations and anions may be used to create positive and negative transmembrane potential respectively.","PeriodicalId":62927,"journal":{"name":"生物物理化学(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70902604","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}
Nicolas Rouleau, Trevor N. Carniello, M. Persinger
Macroscopic productions of “non-locality” or “excess correlations” of dynamic changes within media between two spaces could be utilized as alternative communication systems. Previous experiments have shown that injections of a weak acid within one of two volumes of spring water sharing the same patterned circular magnetic fields with changing angular accelerations separated by non-traditional (5 m) distances were associated with opposite (basic) shifts in pH within the non-injected, non-local volume. In the present experiments, employing a different technology, pairs of beakers separated by 1 m containing either 25 cc, 50 cc, or 100 cc of spring water were placed within toroids generating weak (30, 300 nT) changing acceleration magnetic fields with 1 ms, 2 ms, or 3 ms point durations or a field whose point durations changed. When a proton source (weak acid) was injected into one beaker (local) pH shifts in the other (non-local) beaker exhibit increased acidity for the 3 ms point duration but increased alkalinity for the 1 ms duration. Neither intermittent point durations nor variable point durations for the same volumes of water placed between the two magnetic field-coupled beakers exhibited significant changes from baseline. Contingent upon the point duration of the applied field, the pH shift was consistent with a fixed quantity of decreased free protons (increased pH) or increased protons (decreased pH) in the non-local beakers. The opposite directions of the pH shifts at 1 ms and 3 ms that correspond to quantitative cosmological solutions for electrons and protons suggest these results may reflect a fundamental physical process.
{"title":"Non-Local pH Shifts and Shared Changing Angular Velocity Magnetic Fields: Discrete Energies and the Importance of Point Durations","authors":"Nicolas Rouleau, Trevor N. Carniello, M. Persinger","doi":"10.4236/JBPC.2014.52006","DOIUrl":"https://doi.org/10.4236/JBPC.2014.52006","url":null,"abstract":"Macroscopic productions of “non-locality” or “excess correlations” of dynamic changes within media between two spaces could be utilized as alternative communication systems. Previous experiments have shown that injections of a weak acid within one of two volumes of spring water sharing the same patterned circular magnetic fields with changing angular accelerations separated by non-traditional (5 m) distances were associated with opposite (basic) shifts in pH within the non-injected, non-local volume. In the present experiments, employing a different technology, pairs of beakers separated by 1 m containing either 25 cc, 50 cc, or 100 cc of spring water were placed within toroids generating weak (30, 300 nT) changing acceleration magnetic fields with 1 ms, 2 ms, or 3 ms point durations or a field whose point durations changed. When a proton source (weak acid) was injected into one beaker (local) pH shifts in the other (non-local) beaker exhibit increased acidity for the 3 ms point duration but increased alkalinity for the 1 ms duration. Neither intermittent point durations nor variable point durations for the same volumes of water placed between the two magnetic field-coupled beakers exhibited significant changes from baseline. Contingent upon the point duration of the applied field, the pH shift was consistent with a fixed quantity of decreased free protons (increased pH) or increased protons (decreased pH) in the non-local beakers. The opposite directions of the pH shifts at 1 ms and 3 ms that correspond to quantitative cosmological solutions for electrons and protons suggest these results may reflect a fundamental physical process.","PeriodicalId":62927,"journal":{"name":"生物物理化学(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70902396","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}
The purpose of the present study was to examine the genetic variation in Salamandra infraimmaculata from different breeding site habitats using the Amplified Fragment Length Polymorphism (AFLP) method. The results of the dendogram from a hierarchical cluster analysis show that the grouping of S. infraimmaculata as cluster 5 differs from all the other clusters, including the St1 (Tel-Dan stream) population, which was the most predictable. Five Haplogroups (Hg) were characterized. The mean number of alleles per locus in each population (Ne) ranged from 10.566 (Sp1) to 2.720 (Po6). An average estimated heterozygosity (He) by population ranged from 0.100 (Po6) to 0.186 (St1). Population St1, a permanent breeding site where water was available all year round, exhibited the highest level of polymorphism, while population Po6, from the ephemeral breeding site, exhibited the lowest level of polymorphism. Gene flow between clusters showed that clusters 3 and 4 are sources of migrants and also receive gene flow, while clusters 1 and 2 may be a source of migrants but may not receive much gene flow. A phylogenetic analysis, based on clustering using Nei’s genetic distance, demonstrated that the Tel-Dan population is located on a separate branch within its sub-population. The conclusion of the present study shows that the genetic divergence among isolated populations is not correlated to distance but is affected by the variation of habitats.
{"title":"Genetic Variation in Salamandra infraimmaculata from Different Habitats Using Amplified Fragment Length Polymorphism","authors":"G. Degani, T. Goldberg, E. Nevo","doi":"10.4236/JBPC.2014.52007","DOIUrl":"https://doi.org/10.4236/JBPC.2014.52007","url":null,"abstract":"The purpose of the present study was to examine the genetic variation in Salamandra infraimmaculata from different breeding site habitats using the Amplified Fragment Length Polymorphism (AFLP) method. The results of the dendogram from a hierarchical cluster analysis show that the grouping of S. infraimmaculata as cluster 5 differs from all the other clusters, including the St1 (Tel-Dan stream) population, which was the most predictable. Five Haplogroups (Hg) were characterized. The mean number of alleles per locus in each population (Ne) ranged from 10.566 (Sp1) to 2.720 (Po6). An average estimated heterozygosity (He) by population ranged from 0.100 (Po6) to 0.186 (St1). Population St1, a permanent breeding site where water was available all year round, exhibited the highest level of polymorphism, while population Po6, from the ephemeral breeding site, exhibited the lowest level of polymorphism. Gene flow between clusters showed that clusters 3 and 4 are sources of migrants and also receive gene flow, while clusters 1 and 2 may be a source of migrants but may not receive much gene flow. A phylogenetic analysis, based on clustering using Nei’s genetic distance, demonstrated that the Tel-Dan population is located on a separate branch within its sub-population. The conclusion of the present study shows that the genetic divergence among isolated populations is not correlated to distance but is affected by the variation of habitats.","PeriodicalId":62927,"journal":{"name":"生物物理化学(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70902454","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}
Although heme oxygenase-1 and glutathione play important roles in the antioxidant defense system, the sharing and/or cross-talking of the HO-1 and GSH system remain poorly understood. The object of this study is to determine whether the glutathione system is involved in the antioxidant function of hemin. Hydrogen peroxide decreased the viability of the human leukemic monocyte lymphoma cell line U937. When these cells were pretreated with hemin before the addition of hydrogen peroxide, cell death was prevented. An inhibitor of heme oxygenase-1 or glutathione biosynthesis significantly abolished this protective effect of hemin. These results suggest that both heme oxygenase-1 and glutathione are involved in the protective effects of hemin against U937 cell death, which was induced by hydrogen peroxide. Hemin induced an increase in glutathione levels following the upregulation of the gene expression and protein levels of glutamate-cysteine ligase catalytic subunit. The inhibitor of heme oxigenase-1 inhibited the upregulation of glutamate-cysteine ligase catalytic subunit expression. These results suggest that hemin induces glutathione synthesis through heme oxygenase-1 activation to protect cells from hydrogen peroxide-induced oxidative stress.
{"title":"Hemin Protects U937 Cells from Oxidative Stress via Glutathione Synthesis","authors":"Y. Satoh, Kyohei Oyama, K. Sakurai","doi":"10.4236/JBPC.2014.52003","DOIUrl":"https://doi.org/10.4236/JBPC.2014.52003","url":null,"abstract":"Although heme oxygenase-1 and glutathione play important roles in the antioxidant defense system, the sharing and/or cross-talking of the HO-1 and GSH system remain poorly understood. The object of this study is to determine whether the glutathione system is involved in the antioxidant function of hemin. Hydrogen peroxide decreased the viability of the human leukemic monocyte lymphoma cell line U937. When these cells were pretreated with hemin before the addition of hydrogen peroxide, cell death was prevented. An inhibitor of heme oxygenase-1 or glutathione biosynthesis significantly abolished this protective effect of hemin. These results suggest that both heme oxygenase-1 and glutathione are involved in the protective effects of hemin against U937 cell death, which was induced by hydrogen peroxide. Hemin induced an increase in glutathione levels following the upregulation of the gene expression and protein levels of glutamate-cysteine ligase catalytic subunit. The inhibitor of heme oxigenase-1 inhibited the upregulation of glutamate-cysteine ligase catalytic subunit expression. These results suggest that hemin induces glutathione synthesis through heme oxygenase-1 activation to protect cells from hydrogen peroxide-induced oxidative stress.","PeriodicalId":62927,"journal":{"name":"生物物理化学(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70902700","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}
Trinucleotide repeat expansions (CAG) lead to increase in glutamine residues and hence increase in glutamine stretch. This leads to number of neurodegenerative diseases. Therefore, the conformation of poly Q of varying chain lengths has been investigated by quantum mechanical and molecular dynamics approaches. Glutamine contains amide linkage in the side chain. It is the interaction between side chain amide linkage and the peptide bond of the backbone which dictates the conformational behaviour. Some of the glutamine residues adopt phi psi values corresponding to poly-L-proline type II structure. Not more than three glutamine residues are found to have the same set of values and hence polyglutamine is adopting random coil structure. Carbonyl-carbonyl, CH-O interactions and hydrogen bond formation involving backbone and side chain amide chain linkages are found to contribute to the stability of the adopted structure. In simulation studies due to interaction of water molecules with the amide linkages the values undergo change and this leads to weakening of carbonyl-carbonyl interactions and hydrogen bonds. The conformational behaviour of polyglutamine peptides is shown to be chain length dependent and this may provide some insight regarding the aggregation behaviour of proteins containing poly Q stretch. Possibly this is the first systematic study of the conformational behaviour of polyglutamine peptides.
{"title":"A Unique Conformational Behaviour of Glutamine Peptides","authors":"M. Baskar, M. Shafique, F. S. Nandel","doi":"10.4236/JBPC.2014.52005","DOIUrl":"https://doi.org/10.4236/JBPC.2014.52005","url":null,"abstract":"Trinucleotide repeat expansions (CAG) lead to increase in glutamine residues and hence increase in glutamine stretch. This leads to number of neurodegenerative diseases. Therefore, the conformation of poly Q of varying chain lengths has been investigated by quantum mechanical and molecular dynamics approaches. Glutamine contains amide linkage in the side chain. It is the interaction between side chain amide linkage and the peptide bond of the backbone which dictates the conformational behaviour. Some of the glutamine residues adopt phi psi values corresponding to poly-L-proline type II structure. Not more than three glutamine residues are found to have the same set of values and hence polyglutamine is adopting random coil structure. Carbonyl-carbonyl, CH-O interactions and hydrogen bond formation involving backbone and side chain amide chain linkages are found to contribute to the stability of the adopted structure. In simulation studies due to interaction of water molecules with the amide linkages the values undergo change and this leads to weakening of carbonyl-carbonyl interactions and hydrogen bonds. The conformational behaviour of polyglutamine peptides is shown to be chain length dependent and this may provide some insight regarding the aggregation behaviour of proteins containing poly Q stretch. Possibly this is the first systematic study of the conformational behaviour of polyglutamine peptides.","PeriodicalId":62927,"journal":{"name":"生物物理化学(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70902780","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}
Using a statistical analysis on beta-sheet structures from the Protein Data Bank, characteristic angles within beta-strands were correlated to the nature of the side chains. The twists were computed from the atomic coordinates of five consecutive amino acids’ alpha carbons from single beta-strand sequences. Conditions on the angles for twists to be mainly left-handed are given together with the frequency of occurrence for these non-standard geometrical properties within protein beta-strands. Applications in protein structure prediction and CASP challenges in particular are envisioned by making use of the probabilities of occurrence in protein structures of angle value ranges for given amino acids.
{"title":"Geometrical criteria for left-handed twists within protein beta-strands","authors":"B. Caudron, J. Jestin","doi":"10.4236/JBPC.2014.51002","DOIUrl":"https://doi.org/10.4236/JBPC.2014.51002","url":null,"abstract":"Using a statistical analysis on beta-sheet structures from the Protein Data Bank, characteristic angles within beta-strands were correlated to the nature of the side chains. The twists were computed from the atomic coordinates of five consecutive amino acids’ alpha carbons from single beta-strand sequences. Conditions on the angles for twists to be mainly left-handed are given together with the frequency of occurrence for these non-standard geometrical properties within protein beta-strands. Applications in protein structure prediction and CASP challenges in particular are envisioned by making use of the probabilities of occurrence in protein structures of angle value ranges for given amino acids.","PeriodicalId":62927,"journal":{"name":"生物物理化学(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70902842","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}
K. Hovnanyan, V. Mamikonyan, A. Margaryan, K. Sargsyan, M. Hovnanyan, M. Karagyozyan, K. Karageuzyan
The liver, as the central metabolic organ, plays an important role in metabolism of carbohydrates, lipids and proteins. In the environment, there are many hepatotoxic xenobiotics. CCl4 is a free radical toxic for organelles of hepatocytes. The presented work was studying the character of ultrastructural changes in CCl4-intoxicated hepatocytes as well as the tissue after treatment by grape seed extract (GSE), α-tocopherol (α-T). As a result of cell bioremediation effect and reactions against corruptive factors, the liver has a high regeneration ability.
{"title":"Antioxidants as effective remedies at hepatotoxic action of carbon tetrachloride","authors":"K. Hovnanyan, V. Mamikonyan, A. Margaryan, K. Sargsyan, M. Hovnanyan, M. Karagyozyan, K. Karageuzyan","doi":"10.4236/JBPC.2014.51001","DOIUrl":"https://doi.org/10.4236/JBPC.2014.51001","url":null,"abstract":"The liver, as the central metabolic organ, plays an important role in metabolism of carbohydrates, lipids and proteins. In the environment, there are many hepatotoxic xenobiotics. CCl4 is a free radical toxic for organelles of hepatocytes. The presented work was studying the character of ultrastructural changes in CCl4-intoxicated hepatocytes as well as the tissue after treatment by grape seed extract (GSE), α-tocopherol (α-T). As a result of cell bioremediation effect and reactions against corruptive factors, the liver has a high regeneration ability.","PeriodicalId":62927,"journal":{"name":"生物物理化学(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70902832","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}
D. Yoshida, T. Yokoyama, T. Shimoaki, T. Tomita, T. Yoshida, Yasushi Yamamoto, K. Taga, Ayumi Sumino, Takehisa Dewa, M. Nango, Masato Yamamoto, Zameer Sheravani
Preparation of DPPC lipid monolayer in water trough has been done by dropping method and compared with compression method. Monolayer was studied by surface pressure isotherm, fluorescence microscopy, Brewster angle microscopy, and infrared external reflection spectroscopy. Results of these measurements showed that dropping method gave better results compared to compression method. In dropping method, transition from liquid expanded state to liquid condensed is gradual compared to sharp one in compressed method. During monolayer formation, adjustment and interaction between hydrophilic part of lipid and water and among hydrophobic part of lipid molecule are slow, stable, and more natural as worked out from surface area versus pressure isotherm. At a given molecular area, surface pressure is less compared to compression method thus monolayer is in more fluidic state in dropping method than compression method. The observation was supported by all techniques described above.
{"title":"Morphology observation of dipalmitoyl phosphatidyl choline (DPPC) monolayer on water surface by dropping method","authors":"D. Yoshida, T. Yokoyama, T. Shimoaki, T. Tomita, T. Yoshida, Yasushi Yamamoto, K. Taga, Ayumi Sumino, Takehisa Dewa, M. Nango, Masato Yamamoto, Zameer Sheravani","doi":"10.4236/JBPC.2013.44016","DOIUrl":"https://doi.org/10.4236/JBPC.2013.44016","url":null,"abstract":"Preparation of DPPC lipid monolayer in water trough has been done by dropping method and compared with compression method. Monolayer was studied by surface pressure isotherm, fluorescence microscopy, Brewster angle microscopy, and infrared external reflection spectroscopy. Results of these measurements showed that dropping method gave better results compared to compression method. In dropping method, transition from liquid expanded state to liquid condensed is gradual compared to sharp one in compressed method. During monolayer formation, adjustment and interaction between hydrophilic part of lipid and water and among hydrophobic part of lipid molecule are slow, stable, and more natural as worked out from surface area versus pressure isotherm. At a given molecular area, surface pressure is less compared to compression method thus monolayer is in more fluidic state in dropping method than compression method. The observation was supported by all techniques described above.","PeriodicalId":62927,"journal":{"name":"生物物理化学(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70902651","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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