Umami peptides play important roles in the flavor of fermented broad bean paste(FBBP),and proteases produced by microorganisms contributed to the production of umami peptides.In order to reveal the formation of umami ...Umami peptides play important roles in the flavor of fermented broad bean paste(FBBP),and proteases produced by microorganisms contributed to the production of umami peptides.In order to reveal the formation of umami peptides and their relationships with protease-producing microorganisms during the natural fermentation of FBBP,peptidomics and virtual screening were used to identify and screen umami peptides.Meanwhile,macrogenomics was used to analyze the abundance of microbial-derived protease genes during FBBP fermentation.Then,based on the Pearson correlation coefficient,the correlation network diagram of each protease-producing microorganism with umami peptides was constructed.The results showed that a total of two exopeptidases and four endopeptidases were annotated from FBBP.Staphylococcus,Lactobacillus,Aspergillus,and Weissella can produce most proteases.The species Lactobacillus curvatus,Dyella jiangningensis,Erythrobacter sp.,and unclassified_g_Pantoea had strong correlation with umami peptides,and they may contribute to the process of protein hydrolysis to produce umami peptides.This study is expected to reveal the formation mechanism of umami peptides in FBBP,and the results of this study provided a better understanding of the relationship between proteases,microbiota,and core umami peptides in FBBP,which could help to improve the umami taste of Pixian Douban paste during fermentation.展开更多
Nitrogen(N)loss is a major limiting factor affecting agricultural productivity in saline-alkali soils,with ammonia(NH_(3))volatilization and N leaching being the main sources of N loss.In this study,the dynamics of NH...Nitrogen(N)loss is a major limiting factor affecting agricultural productivity in saline-alkali soils,with ammonia(NH_(3))volatilization and N leaching being the main sources of N loss.In this study,the dynamics of NH_(3)volatilization were measured using the open static chamber method(sponge sampling),alongside the distribution of^(15)N and NO_(3)^(-)-N concentrations in layers,in a 30-cm soil column experiment with vermicompost addition after incorporation of^(15)N-labeled urea in the upper layer(0-10 cm)of a saline-alkali soil.Destructive sampling was conducted on days 20 and 60 of the column experiment to investigate the influencing factors of NH_(3)volatilization and^(15)N/NO_(3)^(-)retention,respectively.The results showed that the addition of vermicompost to saline-alkali soil decreased cumulative NH_(3)volatilization by 45.1%,decreased the^(15)N concentration in the bottom layer(20-30 cm)by 17.1%,and increased the^(15)N concentration in the upper soil by 48.7%.Vermicompost regulated the abundances of amoA,amoC,and nxrA genes,which can decrease NH_(3)volatilization by converting substrate NH_(4)^(+)to NO_(3)^(-).Additionally,Ca^(2+)adsorption is enhanced(increased by 6.2%)by increasing soil cation exchange capacity(increased by 20.6%),thus replacing the adsorption of Na^(+)(decreased by 13.8%)and decreasing the desorption of NH_(4)^(+).Vermicompost enhanced the adsorption of NO_(3)^(-)by increasing Ca^(2+)and Mg^(2+)and decreasing Cl-by 30.4%in the upper soil.This study concluded that vermicompost addition can inhibit N loss by reducing NH_(3)volatilization and improving^(15)N/NO_(3)^(-)retention in saline-alkali soils.展开更多
Biogasification of coal is important for clean utilization of coal. Experiments on the fermentation of single lignite, single straw and their mixture were performed to explore the variation characteristics of gas prod...Biogasification of coal is important for clean utilization of coal. Experiments on the fermentation of single lignite, single straw and their mixture were performed to explore the variation characteristics of gas production potential, microbial community and methanogenic metabolic pathways of mixture. Research has shown that mixed fermentation of lignite and straw significantly promoted biomethane production. The abundance of hydrolytic acidifying functional bacteria genera (Sphaerochaeta, Lentimicrobium) in mixed fermentation was higher than that in the fermentation of single lignite and single straw. The abundance of some key CAZy metabolic enzyme gene sequences in mixed fermentation group was increased, which was favorable to improve methane production. Aceticlastic methanogenesis was the most critical methanogenic pathway and acetic acid pathway was more competitive in methanogenic mode during peak fermentation. Macrogenomics provided theoretical support for the claim that mixed fermentation of coal and straw promoted biomethane metabolism, which was potentially valuable in expanding methanogenesis from mixed fermentation of lignite with different biomasses.展开更多
BACKGROUND Kidney transplantation is the standard treatment for end-stage renal disease.Particularly,rare and specific pathogenic infections which are asymptomatic are often difficult to diagnose,causing delayed and i...BACKGROUND Kidney transplantation is the standard treatment for end-stage renal disease.Particularly,rare and specific pathogenic infections which are asymptomatic are often difficult to diagnose,causing delayed and ineffective treatment and thus seriously affecting prognosis.Tropheryma whipplei(T.whipplei)is a Gram-positive actinomycete widely found in soil,sewage,and other external environments and is present in the population as an asymptomatic pathogen.There is relatively little documented research on T.whipplei in renal transplant patients,and there are no uniform criteria for treating this group of post-transplant patients.This article describes the treatment of a 42-year-old individual with post-transplant T.whipplei infection following kidney transplantation.CASE SUMMARY To analyze clinical features of Whipple’s disease and summarize its diagnosis and treatment effects after renal transplantation.Clinical data of a Whipple’s disease patient treated in the affiliated hospital of Guizhou Medical University were collected and assessed retrospectively.The treatment outcomes and clinical experience were then summarized via literature review.The patient was admitted to the hospital due to recurrent diarrhea for 1 mo,shortness of breath,and 1 wk of fever,after 3 years of renal transplantation.The symptoms of the digestive and respiratory systems were not significantly improved after adjusting immunosuppressive regimen and anti-diarrheal,empirical antibiotic treatments.Bronchoscopic alveolar fluid was collected for meta-genomic next-generation sequencing(mNGS).The deoxyribonucleic acid sequence of Tropheryma whipplei was detected,and Whipple’s disease was diagnosed.Meropenem,ceftriaxone,and other symptomatic treatments were given,and water-electrolyte balance was maintained.Symptoms resolved quickly,and the patient was discharged after 20 d of hospitalization.The compound sulfamethoxazole tablet was continued for 3 mo after discharge.No diarrhea,fever,and other symptoms occurred during the 6-month follow-up.CONCLUSION Whipple’s disease is rare,with no specific symptoms,which makes diagnosis difficult.Polymerase chain reaction or mNGS should be immediately performed when the disease is suspected to confirm the diagnosis.展开更多
基金supported by the Science and Technology Department of Sichuan Province,China(2020YFN0151,23ZDYF3100)Chongqing Science and Technology Commission(cstc2021jscx-cylhX0014).
文摘Umami peptides play important roles in the flavor of fermented broad bean paste(FBBP),and proteases produced by microorganisms contributed to the production of umami peptides.In order to reveal the formation of umami peptides and their relationships with protease-producing microorganisms during the natural fermentation of FBBP,peptidomics and virtual screening were used to identify and screen umami peptides.Meanwhile,macrogenomics was used to analyze the abundance of microbial-derived protease genes during FBBP fermentation.Then,based on the Pearson correlation coefficient,the correlation network diagram of each protease-producing microorganism with umami peptides was constructed.The results showed that a total of two exopeptidases and four endopeptidases were annotated from FBBP.Staphylococcus,Lactobacillus,Aspergillus,and Weissella can produce most proteases.The species Lactobacillus curvatus,Dyella jiangningensis,Erythrobacter sp.,and unclassified_g_Pantoea had strong correlation with umami peptides,and they may contribute to the process of protein hydrolysis to produce umami peptides.This study is expected to reveal the formation mechanism of umami peptides in FBBP,and the results of this study provided a better understanding of the relationship between proteases,microbiota,and core umami peptides in FBBP,which could help to improve the umami taste of Pixian Douban paste during fermentation.
基金supported by the National Key R&D Program of China(No.2021YFD1900901)the National Natural Science Foundation of China(No.32271711).
文摘Nitrogen(N)loss is a major limiting factor affecting agricultural productivity in saline-alkali soils,with ammonia(NH_(3))volatilization and N leaching being the main sources of N loss.In this study,the dynamics of NH_(3)volatilization were measured using the open static chamber method(sponge sampling),alongside the distribution of^(15)N and NO_(3)^(-)-N concentrations in layers,in a 30-cm soil column experiment with vermicompost addition after incorporation of^(15)N-labeled urea in the upper layer(0-10 cm)of a saline-alkali soil.Destructive sampling was conducted on days 20 and 60 of the column experiment to investigate the influencing factors of NH_(3)volatilization and^(15)N/NO_(3)^(-)retention,respectively.The results showed that the addition of vermicompost to saline-alkali soil decreased cumulative NH_(3)volatilization by 45.1%,decreased the^(15)N concentration in the bottom layer(20-30 cm)by 17.1%,and increased the^(15)N concentration in the upper soil by 48.7%.Vermicompost regulated the abundances of amoA,amoC,and nxrA genes,which can decrease NH_(3)volatilization by converting substrate NH_(4)^(+)to NO_(3)^(-).Additionally,Ca^(2+)adsorption is enhanced(increased by 6.2%)by increasing soil cation exchange capacity(increased by 20.6%),thus replacing the adsorption of Na^(+)(decreased by 13.8%)and decreasing the desorption of NH_(4)^(+).Vermicompost enhanced the adsorption of NO_(3)^(-)by increasing Ca^(2+)and Mg^(2+)and decreasing Cl-by 30.4%in the upper soil.This study concluded that vermicompost addition can inhibit N loss by reducing NH_(3)volatilization and improving^(15)N/NO_(3)^(-)retention in saline-alkali soils.
文摘Biogasification of coal is important for clean utilization of coal. Experiments on the fermentation of single lignite, single straw and their mixture were performed to explore the variation characteristics of gas production potential, microbial community and methanogenic metabolic pathways of mixture. Research has shown that mixed fermentation of lignite and straw significantly promoted biomethane production. The abundance of hydrolytic acidifying functional bacteria genera (Sphaerochaeta, Lentimicrobium) in mixed fermentation was higher than that in the fermentation of single lignite and single straw. The abundance of some key CAZy metabolic enzyme gene sequences in mixed fermentation group was increased, which was favorable to improve methane production. Aceticlastic methanogenesis was the most critical methanogenic pathway and acetic acid pathway was more competitive in methanogenic mode during peak fermentation. Macrogenomics provided theoretical support for the claim that mixed fermentation of coal and straw promoted biomethane metabolism, which was potentially valuable in expanding methanogenesis from mixed fermentation of lignite with different biomasses.
基金Supported by Guiyang Science and Technology Program,No.2019-9-1-39.
文摘BACKGROUND Kidney transplantation is the standard treatment for end-stage renal disease.Particularly,rare and specific pathogenic infections which are asymptomatic are often difficult to diagnose,causing delayed and ineffective treatment and thus seriously affecting prognosis.Tropheryma whipplei(T.whipplei)is a Gram-positive actinomycete widely found in soil,sewage,and other external environments and is present in the population as an asymptomatic pathogen.There is relatively little documented research on T.whipplei in renal transplant patients,and there are no uniform criteria for treating this group of post-transplant patients.This article describes the treatment of a 42-year-old individual with post-transplant T.whipplei infection following kidney transplantation.CASE SUMMARY To analyze clinical features of Whipple’s disease and summarize its diagnosis and treatment effects after renal transplantation.Clinical data of a Whipple’s disease patient treated in the affiliated hospital of Guizhou Medical University were collected and assessed retrospectively.The treatment outcomes and clinical experience were then summarized via literature review.The patient was admitted to the hospital due to recurrent diarrhea for 1 mo,shortness of breath,and 1 wk of fever,after 3 years of renal transplantation.The symptoms of the digestive and respiratory systems were not significantly improved after adjusting immunosuppressive regimen and anti-diarrheal,empirical antibiotic treatments.Bronchoscopic alveolar fluid was collected for meta-genomic next-generation sequencing(mNGS).The deoxyribonucleic acid sequence of Tropheryma whipplei was detected,and Whipple’s disease was diagnosed.Meropenem,ceftriaxone,and other symptomatic treatments were given,and water-electrolyte balance was maintained.Symptoms resolved quickly,and the patient was discharged after 20 d of hospitalization.The compound sulfamethoxazole tablet was continued for 3 mo after discharge.No diarrhea,fever,and other symptoms occurred during the 6-month follow-up.CONCLUSION Whipple’s disease is rare,with no specific symptoms,which makes diagnosis difficult.Polymerase chain reaction or mNGS should be immediately performed when the disease is suspected to confirm the diagnosis.
