Propanoic acid accumulated in an ethanol-methane coupled fermentation process affects the ethanol fermentation by Saccharomyces cerevisiae. The effects of propanoic acid on ethanol production were examined in cassava ...Propanoic acid accumulated in an ethanol-methane coupled fermentation process affects the ethanol fermentation by Saccharomyces cerevisiae. The effects of propanoic acid on ethanol production were examined in cassava mash under different pH conditions. Final ethanol concentrations increased when undissociated propanoic acid was <30.0 mmol·L-1 . Propanoic acid, however, stimulated ethanol production, as much as 7.6% under proper conditions, but ethanol fermentation was completely inhibited when undissociated acid was >53.2 mmol·L-1 . Therefore, the potential inhibitory effect of propanoic acid on ethanol fermentation may be avoided by controlling the undissociated acid concentrations through elevated medium pH. Biomass and glycerol production decreased with propanoic acid in the medium, partly contributing to increased ethanol concentration.展开更多
AIM： To investigate ASCA production over time in CD and murine colitis in order to further our understanding of their etiology. MATERIALS AND METHODS： Sixty-six CD patients were compared to ulcerative colitis （UC）...AIM： To investigate ASCA production over time in CD and murine colitis in order to further our understanding of their etiology. MATERIALS AND METHODS： Sixty-six CD patients were compared to ulcerative colitis （UC） and irritable bowel syndrome patients with respect to ASCA production as measured by ELISA. ASCA IgG or IgA positivity as well as change in titers over a period of up to 3 years （△tgG/A） was correlated with clinical parameters such as CD activity index （CDM） and C-reactive protein levels （CRP）. Moreover, two murine models of colitis （DSS and IL-10 knock out） were compared to control animals with respect to ASCA titers after oral yeast exposure. RESULTS： ASCA IgG and IgA titers are stable over time in CD and non-CD patients. Fistular disease was associated with a higher rate of ASCA IgA positivity （P = 0.014）. Ileal disease was found to have a significant influence on the △tgG of ASCA （P = 0.032）. There was no correlation found between ASCA positivity or △tgG/A and clinical parameters of CD： CDAI and CRP. In mice, neither healthy animals nor animals with DSS-induced or spontaneous colitis exhibited a marked increase in ASCA titers after high-dose yeast exposure. On the other hand, mice immunized intraperitoneally with mannan plus adjuvant showed a marked and significant increase in ASCA titers compared to adjuvant-only immunized controls （P = 0.014）. CONCLUSION： The propensity to produce ASCA in a subgroup of CD patients is largely genetically predetermined as evidenced by their stability and lack of correlation with clinical disease activity parameters. Furthermore, in animal models of colitis, mere oral exposure of mice to yeast does not lead to the induction of marked ASCA titers irrespective of concomitant colonic inflammation. Hence, environment may play only a minor role in inducing ASCA.展开更多
The differential diagnosis of Behcet's disease(BD) from inflammatory bowel disease(IBD) is sometimes difficult and challenging.Hereby,we suggested the utility of anti-saccharomyces cerevisiae antibody(ASCA) and an...The differential diagnosis of Behcet's disease(BD) from inflammatory bowel disease(IBD) is sometimes difficult and challenging.Hereby,we suggested the utility of anti-saccharomyces cerevisiae antibody(ASCA) and anti-neutrophilic cytoplasmic antibody(p-ANCA) in the differential diagnosis of BD from IBD.展开更多
Background As Holstein calves are susceptible to gastrointestinal disorders during the first week of life,understanding how intestinal immune function develops in neonatal calves is important to promote better intesti...Background As Holstein calves are susceptible to gastrointestinal disorders during the first week of life,understanding how intestinal immune function develops in neonatal calves is important to promote better intestinal health.Feeding probiotics in early life may contribute to host intestinal health by facilitating beneficial bacteria colonization and developing intestinal immune function.The objective of this study was to characterize the impact of early life yeast supplementation and growth on colon mucosa-attached bacteria and host immune function.Results Twenty Holstein bull calves received no supplementation(CON)or Saccharomyces cerevisiae boulardii(SCB)from birth to 5 d of life.Colon tissue biopsies were taken within 2 h of life(D0)before the first colostrum feeding and 3 h after the morning feeding at d 5 of age(D5)to analyze mucosa-attached bacteria and colon transcriptome.Metagenome sequencing showed that there was no difference inαandβdiversity of mucosa-attached bacteria between day and treatment,but bacteria related to diarrhea were more abundant in the colon mucosa on D0 compared to D5.In addition,q PCR indicated that the absolute abundance of Escherichia coli(E.coli)decreased in the colon mucosa on D5 compared to D0;however,that of Bifidobacterium,Lactobacillus,and Faecalibacterium prausnitzii,which could competitively exclude E.coli,increased in the colon mucosa on D5 compared to D0.RNA-sequencing showed that there were no differentially expressed genes between CON and SCB,but suggested that pathways related to viral infection such as“Interferon Signaling”were activated in the colon mucosa of D5 compared to D0.Conclusions Growth affected mucosa-attached bacteria and host immune function in the colon mucosa during the first 5 d of life in dairy calves independently of SCB supplementation.During early life,opportunistic pathogens may decrease due to intestinal environmental changes by beneficial bacteria and/or host immune function.Predicted activation of immune function-related pathways may be the result of host immune function development or suggest other antigens in the intestine during early life.Further studies focusing on the other antigens and host immune function in the colon mucosa are required to better understand intestinal immune function development.展开更多
AIM： To test whether humoral immune reaction against mycobacteria may play a role in anti- Saccharomyces cerevisiae antibodies （ASCA） generation in Crohn＇s disease （CD） and/or whether it correlates with clinical...AIM： To test whether humoral immune reaction against mycobacteria may play a role in anti- Saccharomyces cerevisiae antibodies （ASCA） generation in Crohn＇s disease （CD） and/or whether it correlates with clinical subtypes. METHODS： The dominant ASCA epitope was detected by Galanthus nivalis lectin （GNL）-binding assay. ASCA and IgG against mycobacterial lysates （M avium, M smegmatis, M chelonae, M bovis BCG M avium ssp. paratuberculosis （MAP）] or purified lipoarabinomannans （LAM） were detected by ELISA. ASCA and anti-mycobacterial antibodies were affinity purified to assess cross-reactivities. Anti-mycobacterial IgG were induced by BCG-infection of mice. RESULTS： GNL bound to different extents to mycobacterial lysates, abundantly to purified mannosecapped （Man） LAM from M tuberculosis, but not to uncapped LAM from M srnegrnatis. Fifteen to 45% of CD patients but only 0%-6% of controls were seropositive against different mycobacterial antigens. Anti-mycobacterial IgG correlated with ASCA （r = 0.37-0.64; P = 0.003-P 〈 0.001）. ASCA-positivity and deficiency for mannan-binding lectin synergistically associated with anti-mycobacterial IgG. In some patients, anti-mycobacterial antibodies represent crossreactive ASCA. Vice-versa, the predominant fraction of ASCA did not cross-react with mycobacteria. Finally, fistulizing disease associated with antibodies against M avium, M smegmatis and MAP （P = 0.024, 0.004 and 0.045, respectively）. CONCLUSION： Similar to ASCA, seroreactivity against mycobacteria may define CD patients with complicated disease and a predisposition for immune responses against ubiquitous antigens. While in some patients anti-mycobacterial antibodies strongly cross-react with yeast mannan; these cross-reactive antibodies only represent a minor fraction of total ASCA. Thus, mycobacterial infection unlikely plays a role in ASCA induction.展开更多
MCM10 protein is an essential replication factor involved in the initiation of DNA replication. A mcm10 mutant (mcm10-1) of budding yeast shows a growth arrest at 37 degrees C. In the present work, we have isolated a ...MCM10 protein is an essential replication factor involved in the initiation of DNA replication. A mcm10 mutant (mcm10-1) of budding yeast shows a growth arrest at 37 degrees C. In the present work, we have isolated a mcm10-1 suppressor strain, which grows at 37 degrees C. Interestingly, this mcm10-1 suppressor undergoes cell cycle arrest at 14 degrees C. A novel gene, YLR003c, is identified by high-copy complementation of this suppressor. We called it as Cms1 (Complementation of Mcm 10 Suppressor). Furthermore, the experiments of transformation show that cells of mcm10-1 suppressor with high-copy plasmid but not low-copy plasmid grow at 14 degrees C, indicating that overexpression of Cms1 can rescue the growth arrest of this mcm10 suppressor at non-permissive temperature. These results suggest that CMS1 protein may functionally interact with MCM10 protein and play a role in the regulation of DNA replication and cell cycle control.展开更多
基金Supported by the National High Technology Research and Development Program of China (2008AA10Z338)
文摘Propanoic acid accumulated in an ethanol-methane coupled fermentation process affects the ethanol fermentation by Saccharomyces cerevisiae. The effects of propanoic acid on ethanol production were examined in cassava mash under different pH conditions. Final ethanol concentrations increased when undissociated propanoic acid was <30.0 mmol·L-1 . Propanoic acid, however, stimulated ethanol production, as much as 7.6% under proper conditions, but ethanol fermentation was completely inhibited when undissociated acid was >53.2 mmol·L-1 . Therefore, the potential inhibitory effect of propanoic acid on ethanol fermentation may be avoided by controlling the undissociated acid concentrations through elevated medium pH. Biomass and glycerol production decreased with propanoic acid in the medium, partly contributing to increased ethanol concentration.
基金Supported by the Swiss National Science Foundation grant nu SNSF 31-59031.99 to F. Seibold
文摘AIM： To investigate ASCA production over time in CD and murine colitis in order to further our understanding of their etiology. MATERIALS AND METHODS： Sixty-six CD patients were compared to ulcerative colitis （UC） and irritable bowel syndrome patients with respect to ASCA production as measured by ELISA. ASCA IgG or IgA positivity as well as change in titers over a period of up to 3 years （△tgG/A） was correlated with clinical parameters such as CD activity index （CDM） and C-reactive protein levels （CRP）. Moreover, two murine models of colitis （DSS and IL-10 knock out） were compared to control animals with respect to ASCA titers after oral yeast exposure. RESULTS： ASCA IgG and IgA titers are stable over time in CD and non-CD patients. Fistular disease was associated with a higher rate of ASCA IgA positivity （P = 0.014）. Ileal disease was found to have a significant influence on the △tgG of ASCA （P = 0.032）. There was no correlation found between ASCA positivity or △tgG/A and clinical parameters of CD： CDAI and CRP. In mice, neither healthy animals nor animals with DSS-induced or spontaneous colitis exhibited a marked increase in ASCA titers after high-dose yeast exposure. On the other hand, mice immunized intraperitoneally with mannan plus adjuvant showed a marked and significant increase in ASCA titers compared to adjuvant-only immunized controls （P = 0.014）. CONCLUSION： The propensity to produce ASCA in a subgroup of CD patients is largely genetically predetermined as evidenced by their stability and lack of correlation with clinical disease activity parameters. Furthermore, in animal models of colitis, mere oral exposure of mice to yeast does not lead to the induction of marked ASCA titers irrespective of concomitant colonic inflammation. Hence, environment may play only a minor role in inducing ASCA.
文摘The differential diagnosis of Behcet's disease(BD) from inflammatory bowel disease(IBD) is sometimes difficult and challenging.Hereby,we suggested the utility of anti-saccharomyces cerevisiae antibody(ASCA) and anti-neutrophilic cytoplasmic antibody(p-ANCA) in the differential diagnosis of BD from IBD.
基金supported by funding from Lallemand Health Solution(Mirabel,QC)Alberta Milk(Edmonton,AB)+3 种基金the Saskatoon Colostrum Co.Ltd.(Saskatoon,SK)the Natural Sciences and Engineering Research Council of Canada(Ottawa,ON)supported by a Mitacs Accelerate Program from Mitacs Canada(Toronto,ON)Lallemand SAS(Blagnac,France)。
文摘Background As Holstein calves are susceptible to gastrointestinal disorders during the first week of life,understanding how intestinal immune function develops in neonatal calves is important to promote better intestinal health.Feeding probiotics in early life may contribute to host intestinal health by facilitating beneficial bacteria colonization and developing intestinal immune function.The objective of this study was to characterize the impact of early life yeast supplementation and growth on colon mucosa-attached bacteria and host immune function.Results Twenty Holstein bull calves received no supplementation(CON)or Saccharomyces cerevisiae boulardii(SCB)from birth to 5 d of life.Colon tissue biopsies were taken within 2 h of life(D0)before the first colostrum feeding and 3 h after the morning feeding at d 5 of age(D5)to analyze mucosa-attached bacteria and colon transcriptome.Metagenome sequencing showed that there was no difference inαandβdiversity of mucosa-attached bacteria between day and treatment,but bacteria related to diarrhea were more abundant in the colon mucosa on D0 compared to D5.In addition,q PCR indicated that the absolute abundance of Escherichia coli(E.coli)decreased in the colon mucosa on D5 compared to D0;however,that of Bifidobacterium,Lactobacillus,and Faecalibacterium prausnitzii,which could competitively exclude E.coli,increased in the colon mucosa on D5 compared to D0.RNA-sequencing showed that there were no differentially expressed genes between CON and SCB,but suggested that pathways related to viral infection such as“Interferon Signaling”were activated in the colon mucosa of D5 compared to D0.Conclusions Growth affected mucosa-attached bacteria and host immune function in the colon mucosa during the first 5 d of life in dairy calves independently of SCB supplementation.During early life,opportunistic pathogens may decrease due to intestinal environmental changes by beneficial bacteria and/or host immune function.Predicted activation of immune function-related pathways may be the result of host immune function development or suggest other antigens in the intestine during early life.Further studies focusing on the other antigens and host immune function in the colon mucosa are required to better understand intestinal immune function development.
基金The Swiss National Science Foundation grant No. SNSF 3200B0-107527/1 to F. Seibold
文摘AIM： To test whether humoral immune reaction against mycobacteria may play a role in anti- Saccharomyces cerevisiae antibodies （ASCA） generation in Crohn＇s disease （CD） and/or whether it correlates with clinical subtypes. METHODS： The dominant ASCA epitope was detected by Galanthus nivalis lectin （GNL）-binding assay. ASCA and IgG against mycobacterial lysates （M avium, M smegmatis, M chelonae, M bovis BCG M avium ssp. paratuberculosis （MAP）] or purified lipoarabinomannans （LAM） were detected by ELISA. ASCA and anti-mycobacterial antibodies were affinity purified to assess cross-reactivities. Anti-mycobacterial IgG were induced by BCG-infection of mice. RESULTS： GNL bound to different extents to mycobacterial lysates, abundantly to purified mannosecapped （Man） LAM from M tuberculosis, but not to uncapped LAM from M srnegrnatis. Fifteen to 45% of CD patients but only 0%-6% of controls were seropositive against different mycobacterial antigens. Anti-mycobacterial IgG correlated with ASCA （r = 0.37-0.64; P = 0.003-P 〈 0.001）. ASCA-positivity and deficiency for mannan-binding lectin synergistically associated with anti-mycobacterial IgG. In some patients, anti-mycobacterial antibodies represent crossreactive ASCA. Vice-versa, the predominant fraction of ASCA did not cross-react with mycobacteria. Finally, fistulizing disease associated with antibodies against M avium, M smegmatis and MAP （P = 0.024, 0.004 and 0.045, respectively）. CONCLUSION： Similar to ASCA, seroreactivity against mycobacteria may define CD patients with complicated disease and a predisposition for immune responses against ubiquitous antigens. While in some patients anti-mycobacterial antibodies strongly cross-react with yeast mannan; these cross-reactive antibodies only represent a minor fraction of total ASCA. Thus, mycobacterial infection unlikely plays a role in ASCA induction.
文摘MCM10 protein is an essential replication factor involved in the initiation of DNA replication. A mcm10 mutant (mcm10-1) of budding yeast shows a growth arrest at 37 degrees C. In the present work, we have isolated a mcm10-1 suppressor strain, which grows at 37 degrees C. Interestingly, this mcm10-1 suppressor undergoes cell cycle arrest at 14 degrees C. A novel gene, YLR003c, is identified by high-copy complementation of this suppressor. We called it as Cms1 (Complementation of Mcm 10 Suppressor). Furthermore, the experiments of transformation show that cells of mcm10-1 suppressor with high-copy plasmid but not low-copy plasmid grow at 14 degrees C, indicating that overexpression of Cms1 can rescue the growth arrest of this mcm10 suppressor at non-permissive temperature. These results suggest that CMS1 protein may functionally interact with MCM10 protein and play a role in the regulation of DNA replication and cell cycle control.
基金国家自然科学基金项目(No.20576013)国家高技术研究发展计划(863)项目(Nos.2006AA020102+4 种基金2006AA020103 and 2006AA020201)国家重点基础研究发展计划(973)项目(Nos.2007CB7078042007CB714304)北京市自然科学基金(No.2071002)北京市科技计划项目(No.D0205004040211)资助~~
文摘利用酿酒酵母菌株高密度发酵法生产S-腺苷蛋氨酸关键的影响因素之一是前体L-蛋氨酸的补加策略。本研究采用一支经过常规诱变处理的S-腺苷蛋氨酸优势积累菌株酿酒酵母SAM0801,通过5 L发酵罐高密度发酵实验研究,考察了6种补加策略,最终确定了L-蛋氨酸的加入时机为30 h左右,当菌体干重达到100 g/L时,补加量为每罐40 g L-蛋氨酸,发酵58 h左右达到最高生物量干重168 g/L,产量14.48 g/L。
