The traditional nutritional and medical hemp(Cannabis sativa L.)seed protein were explored for the discovery and directional preparation of new xanthine oxidase inhibitory(XOI)peptides by structure-based virtual scree...The traditional nutritional and medical hemp(Cannabis sativa L.)seed protein were explored for the discovery and directional preparation of new xanthine oxidase inhibitory(XOI)peptides by structure-based virtual screening,compound synthesis,in vitro bioassay and proteolysis.Six subtypes of hemp seed edestin and albumin were in silico hydrolyzed by 29 proteases,and 192 encrypted bioactive peptides were screened out.Six peptides showed to be XOI peptides,of which four(about 67%)were released by elastase hydrolysis.The peptide DDNPRRFY displayed the highest XOI activity(IC50=(2.10±0.06)mg/mL),acting as a mixed inhibitor.The pancreatic elastase directionally prepared XOI hemp seed protein hydrolysates,from which 6 high-abundance XOI peptides encrypted 3 virtually-screened ones including the DDNPRRFY.The novel outstanding hemp seed protein-derived XOI peptides and their virtual screening and directed preparation methods provide a promising and applicable approach to conveniently and efficiently explore food-derived bioactive peptides.展开更多
Dry-cured meat products are considerably popular around the world due to unique flavor.Proteolysis is one of the enzymatic reactions from which flavor substances are derived,which is affected by endogenous proteases.T...Dry-cured meat products are considerably popular around the world due to unique flavor.Proteolysis is one of the enzymatic reactions from which flavor substances are derived,which is affected by endogenous proteases.The purpose aimed to reveal the potential relationship between endogenous proteases and key flavor substances in dry-cured pork coppa in this paper.The dynamic changes of endogenous proteases activity,free amino acids,and volatiles during dry-cured pork coppa processing were characterized.The results showed that 5 kinds of free amino acids,Glu,Lys,Val,Ala,and Leu,were identified as significant contributors to taste.Meanwhile,key volatiles,such as hexanal,nonanal,octanal,benzaldehyde,3-methyl butanoic acid,2-methyl propanoic acid,and ethyl octanoate,greatly contributed to the flavor characteristics of dry-cured pork coppa.Further partial correlation analysis was performed to better elucidate the relationship among parameters.The results revealed that close relationship between endogenous proteases and key substances.RAP not only significantly affected the accumulation of key active-amino acids,but also affected the accumulation of ethyl octanoate,2,3-pentanedione,and 2,3-octanedione by regulating the accumulation of octanoic acid and Leu.In addition,cathepsin B and D,DPP II,DPP IV and RAP notably affected accumulation of hexanal.展开更多
Sourdough is often considered a healthy choice and quality improver for use in cereal production due to its unique microbial composition and fermentation properties.During sourdough fermentation of cereals,biotransfor...Sourdough is often considered a healthy choice and quality improver for use in cereal production due to its unique microbial composition and fermentation properties.During sourdough fermentation of cereals,biotransformation of nutrients occurs,resulting in notable changes to proteins,carbohydrates,fats,vitamins,and minerals.Each nutrient undergoes specific transformations,providing various advantages for human health.Proteins undergo hydrolysis to produce small molecular weight peptides and amino acids that are more easily digested and absorbed by the human body.Carbohydrates break down to improve the digestibility and absorption of cereals and lower the glycemic index.Fatty acids experience oxidation to produce new substances with health benefits.Additionally,the application of sourdough fermentation can enhance the texture,flavor,and nutritional value of cereal foods while also extending their shelf life and improving food safety.In conclusion,sourdough fermentation has a broad range of applications in cereal food processing.Further research is encouraged to investigate the mechanisms and processes of sourdough fermentation to develop even more nutritious,healthy,and flavorful cereal-based foods.展开更多
Aging is a popular method used by meat industry for improving the sensory attributes of meat.Despite the advent of many novel technologies,aging has not lost its charm and is still widely used commercially as a post-m...Aging is a popular method used by meat industry for improving the sensory attributes of meat.Despite the advent of many novel technologies,aging has not lost its charm and is still widely used commercially as a post-mortem intervention for tenderization.Aging improves the tenderness of meat through disruption of the muscle structure by intracellular proteolytic systems.Muscles undergo various molecular changes that cause proteolysis of key myofibrillar and cytoskeletal proteins,disrupting the overall integrity of muscle cells.Although several endogenous proteolytic systems are capable of post-mortem proteolysis,a great body of scientific evidence supports a major role for the calpain system.Calpains are intracellular calcium-dependent cysteine proteases found in most eukaryotes.At least three calpains(μ-and m-calpains and calpain 3)and calpastatin,their specific endogenous inhibitor,are found in muscle.They are known to be involved in the proteolysis of functionally relevant structural proteins such as the myofibrillar proteins and cytoskeletal anchorage complexes.These ubiquitous proteases are also present in mitochondria and play important roles in a variety of pathophysiological conditions including apoptotic and necrotic cell death phenomena.This review discusses the role and contribution of the calpain system and the factors that influence calpain activity during aging.展开更多
Objective.To study the exact effects and characteristics of a constitutively active myosin light chain kinase fragment (MLCKF)on Ca 2+ -CaM dependent phosphorylation of myosin light chains(CDPM)of smooth muscle.Method...Objective.To study the exact effects and characteristics of a constitutively active myosin light chain kinase fragment (MLCKF)on Ca 2+ -CaM dependent phosphorylation of myosin light chains(CDPM)of smooth muscle.Methods.Proteolysis of myosin light chain kinase(MLCK)by trypsin was used to obtain the con-stitutively active fragment of MLCK;Western blot was applied to demonstrate the homogeneity of typsin-digested MLCK fragments and intact MLCK.The phosphorylation of myosin light chains was detected us-ing SDS-PAGE and Scoin Image Software,and myosin Mg 2+ -ATPase activities were measured using spec-trophotometry to observe the characteristics of MLCKF in phosphorylating myosin light chains and stimu-lating myosin Mg 2+ -ATPase activities compared with intact MLCK.Results.Our assay demonstrated that MLCKF had a specific activity on CDPM.We also found that the extent of CDPM by MLCKF was greater than that by intact MLCK at different concentrations,differ-ent incubation time and different incubation temperatures.CDPM by MLCKF was also less influenced by the change of ionic strength of KCl than CDPM by intact MLCK.Mg 2+ -ATPase activities of phosphorylat-ed myosin light chains by MLCKF were higher than those by MLCK at different concentrations and dif-ferent reaction time.These differences were statistically significant ( P<0.01, P<0.05).Conclusion.MLCKF not only possessed a specific activity on CDPM but also was more efficient than MLCK in phosphorylating myosin light chains and stimulating myosin Mg 2+ -ATPase activities.Our results suggested that MLCKF possibly plays a certain role in smooth muscle contraction-relaxation cycle.展开更多
Drug discovery is a crucial part of human healthcare and has dramatically benefited human lifespan and life quality in recent centuries, however, it is usually time-and effort-consuming. Structural biology has been de...Drug discovery is a crucial part of human healthcare and has dramatically benefited human lifespan and life quality in recent centuries, however, it is usually time-and effort-consuming. Structural biology has been demonstrated as a powerful tool to accelerate drug development. Among different techniques, cryo-electron microscopy(cryo-EM) is emerging as the mainstream of structure determination of biomacromolecules in the past decade and has received increasing attention from the pharmaceutical industry. Although cryo-EM still has limitations in resolution, speed and throughput, a growing number of innovative drugs are being developed with the help of cryo-EM. Here, we aim to provide an overview of how cryo-EM techniques are applied to facilitate drug discovery. The development and typical workflow of cryo-EM technique will be briefly introduced, followed by its specific applications in structure-based drug design, fragment-based drug discovery, proteolysis targeting chimeras, antibody drug development and drug repurposing. Besides cryo-EM, drug discovery innovation usually involves other state-of-the-art techniques such as artificial intelligence(AI), which is increasingly active in diverse areas. The combination of cryo-EM and AI provides an opportunity to minimize limitations of cryo-EM such as automation, throughput and interpretation of mediumresolution maps, and tends to be the new direction of future development of cryo-EM. The rapid development of cryo-EM will make it as an indispensable part of modern drug discovery.展开更多
基金funded by National Natural Science Foundation of China(21868003)Bama County Program for Talents in Science and Technology(BaRenKe20210045).
文摘The traditional nutritional and medical hemp(Cannabis sativa L.)seed protein were explored for the discovery and directional preparation of new xanthine oxidase inhibitory(XOI)peptides by structure-based virtual screening,compound synthesis,in vitro bioassay and proteolysis.Six subtypes of hemp seed edestin and albumin were in silico hydrolyzed by 29 proteases,and 192 encrypted bioactive peptides were screened out.Six peptides showed to be XOI peptides,of which four(about 67%)were released by elastase hydrolysis.The peptide DDNPRRFY displayed the highest XOI activity(IC50=(2.10±0.06)mg/mL),acting as a mixed inhibitor.The pancreatic elastase directionally prepared XOI hemp seed protein hydrolysates,from which 6 high-abundance XOI peptides encrypted 3 virtually-screened ones including the DDNPRRFY.The novel outstanding hemp seed protein-derived XOI peptides and their virtual screening and directed preparation methods provide a promising and applicable approach to conveniently and efficiently explore food-derived bioactive peptides.
基金financially supported by the National Natural Science Foundation of China(32001728,32172248)the Taishan Industrial Experts Program+1 种基金the Guizhou High-level Innovative Talent Training Project(Qianke Cooperation Platform Talent number[2016]5662)Guizhou Science and Technology Innovation Talent Team of Ecological Characteristic Meat Products.(QKHPTRC[2020]5004)。
文摘Dry-cured meat products are considerably popular around the world due to unique flavor.Proteolysis is one of the enzymatic reactions from which flavor substances are derived,which is affected by endogenous proteases.The purpose aimed to reveal the potential relationship between endogenous proteases and key flavor substances in dry-cured pork coppa in this paper.The dynamic changes of endogenous proteases activity,free amino acids,and volatiles during dry-cured pork coppa processing were characterized.The results showed that 5 kinds of free amino acids,Glu,Lys,Val,Ala,and Leu,were identified as significant contributors to taste.Meanwhile,key volatiles,such as hexanal,nonanal,octanal,benzaldehyde,3-methyl butanoic acid,2-methyl propanoic acid,and ethyl octanoate,greatly contributed to the flavor characteristics of dry-cured pork coppa.Further partial correlation analysis was performed to better elucidate the relationship among parameters.The results revealed that close relationship between endogenous proteases and key substances.RAP not only significantly affected the accumulation of key active-amino acids,but also affected the accumulation of ethyl octanoate,2,3-pentanedione,and 2,3-octanedione by regulating the accumulation of octanoic acid and Leu.In addition,cathepsin B and D,DPP II,DPP IV and RAP notably affected accumulation of hexanal.
基金supported by the Graduate Education Innovation and Quality Improvement Project of Henan University(No.SYLYC2023185).
文摘Sourdough is often considered a healthy choice and quality improver for use in cereal production due to its unique microbial composition and fermentation properties.During sourdough fermentation of cereals,biotransformation of nutrients occurs,resulting in notable changes to proteins,carbohydrates,fats,vitamins,and minerals.Each nutrient undergoes specific transformations,providing various advantages for human health.Proteins undergo hydrolysis to produce small molecular weight peptides and amino acids that are more easily digested and absorbed by the human body.Carbohydrates break down to improve the digestibility and absorption of cereals and lower the glycemic index.Fatty acids experience oxidation to produce new substances with health benefits.Additionally,the application of sourdough fermentation can enhance the texture,flavor,and nutritional value of cereal foods while also extending their shelf life and improving food safety.In conclusion,sourdough fermentation has a broad range of applications in cereal food processing.Further research is encouraged to investigate the mechanisms and processes of sourdough fermentation to develop even more nutritious,healthy,and flavorful cereal-based foods.
文摘Aging is a popular method used by meat industry for improving the sensory attributes of meat.Despite the advent of many novel technologies,aging has not lost its charm and is still widely used commercially as a post-mortem intervention for tenderization.Aging improves the tenderness of meat through disruption of the muscle structure by intracellular proteolytic systems.Muscles undergo various molecular changes that cause proteolysis of key myofibrillar and cytoskeletal proteins,disrupting the overall integrity of muscle cells.Although several endogenous proteolytic systems are capable of post-mortem proteolysis,a great body of scientific evidence supports a major role for the calpain system.Calpains are intracellular calcium-dependent cysteine proteases found in most eukaryotes.At least three calpains(μ-and m-calpains and calpain 3)and calpastatin,their specific endogenous inhibitor,are found in muscle.They are known to be involved in the proteolysis of functionally relevant structural proteins such as the myofibrillar proteins and cytoskeletal anchorage complexes.These ubiquitous proteases are also present in mitochondria and play important roles in a variety of pathophysiological conditions including apoptotic and necrotic cell death phenomena.This review discusses the role and contribution of the calpain system and the factors that influence calpain activity during aging.
文摘Objective.To study the exact effects and characteristics of a constitutively active myosin light chain kinase fragment (MLCKF)on Ca 2+ -CaM dependent phosphorylation of myosin light chains(CDPM)of smooth muscle.Methods.Proteolysis of myosin light chain kinase(MLCK)by trypsin was used to obtain the con-stitutively active fragment of MLCK;Western blot was applied to demonstrate the homogeneity of typsin-digested MLCK fragments and intact MLCK.The phosphorylation of myosin light chains was detected us-ing SDS-PAGE and Scoin Image Software,and myosin Mg 2+ -ATPase activities were measured using spec-trophotometry to observe the characteristics of MLCKF in phosphorylating myosin light chains and stimu-lating myosin Mg 2+ -ATPase activities compared with intact MLCK.Results.Our assay demonstrated that MLCKF had a specific activity on CDPM.We also found that the extent of CDPM by MLCKF was greater than that by intact MLCK at different concentrations,differ-ent incubation time and different incubation temperatures.CDPM by MLCKF was also less influenced by the change of ionic strength of KCl than CDPM by intact MLCK.Mg 2+ -ATPase activities of phosphorylat-ed myosin light chains by MLCKF were higher than those by MLCK at different concentrations and dif-ferent reaction time.These differences were statistically significant ( P<0.01, P<0.05).Conclusion.MLCKF not only possessed a specific activity on CDPM but also was more efficient than MLCK in phosphorylating myosin light chains and stimulating myosin Mg 2+ -ATPase activities.Our results suggested that MLCKF possibly plays a certain role in smooth muscle contraction-relaxation cycle.
基金funded by the National Natural Science Foundation of China (NSFC, 31900046, 81972085, 82172465 and 32161133022)the Guangdong Provincial Key Laboratory of Advanced Biomaterials (2022B1212010003)+7 种基金the National Science and Technology Innovation 2030 Major Program (2022ZD0211900)the Shenzhen Key Laboratory of Computer Aided Drug Discovery (ZDSYS20201230165400001)the Chinese Academy of Science President’s International Fellowship Initiative (PIFI)(2020FSB0003)the Guangdong Retired Expert (granted by Guangdong Province)the Shenzhen Pengcheng ScientistNSFC-SNSF Funding (32161133022)Alpha Mol&SIAT Joint LaboratoryShenzhen Government Top-talent Working Funding and Guangdong Province Academician Work Funding。
文摘Drug discovery is a crucial part of human healthcare and has dramatically benefited human lifespan and life quality in recent centuries, however, it is usually time-and effort-consuming. Structural biology has been demonstrated as a powerful tool to accelerate drug development. Among different techniques, cryo-electron microscopy(cryo-EM) is emerging as the mainstream of structure determination of biomacromolecules in the past decade and has received increasing attention from the pharmaceutical industry. Although cryo-EM still has limitations in resolution, speed and throughput, a growing number of innovative drugs are being developed with the help of cryo-EM. Here, we aim to provide an overview of how cryo-EM techniques are applied to facilitate drug discovery. The development and typical workflow of cryo-EM technique will be briefly introduced, followed by its specific applications in structure-based drug design, fragment-based drug discovery, proteolysis targeting chimeras, antibody drug development and drug repurposing. Besides cryo-EM, drug discovery innovation usually involves other state-of-the-art techniques such as artificial intelligence(AI), which is increasingly active in diverse areas. The combination of cryo-EM and AI provides an opportunity to minimize limitations of cryo-EM such as automation, throughput and interpretation of mediumresolution maps, and tends to be the new direction of future development of cryo-EM. The rapid development of cryo-EM will make it as an indispensable part of modern drug discovery.
