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Paul J Weimer - One of the best experts on this subject based on the ideXlab platform.
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quantitative analysis of cellulose degradation and growth of Cellulolytic Bacteria in the rumen
FEMS Microbiology Ecology, 2009Co-Authors: James B Russell, R E Muck, Paul J WeimerAbstract:Ruminant animals digest cellulose via a symbiotic relationship with ruminal microorganisms. Because feedstuffs only remain in the rumen for a short time, the rate of cellulose digestion must be very rapid. This speed is facilitated by rumination, a process that returns food to the mouth to be rechewed. By decreasing particle size, the cellulose surface area can be increased by up to 106-fold. The amount of cellulose digested is then a function of two competing rates, namely the digestion rate (Kd) and the rate of passage of solids from the rumen (Kp). Estimation of Bacterial growth on cellulose is complicated by several factors: (1) energy must be expended for maintenance and growth of the cells, (2) only adherent cells are capable of degrading cellulose and (3) adherent cells can provide nonadherent cells with cellodextrins. Additionally, when ruminants are fed large amounts of cereal grain along with fiber, ruminal pH can decrease to a point where Cellulolytic Bacteria no longer grow. A dynamic model based on stella® software is presented. This model evaluates all of the major aspects of ruminal cellulose degradation: (1) ingestion, digestion and passage of feed particles, (2) maintenance and growth of Cellulolytic Bacteria and (3) pH effects.
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competition among three predominant ruminal Cellulolytic Bacteria in the absence or presence of non Cellulolytic Bacteria
Microbiology, 2001Co-Authors: Junqin Chen, Paul J WeimerAbstract:Competition among three species of ruminal Cellulolytic Bacteria ‐ Fibrobacter succinogenes S85, Ruminococcus flavefaciens FD-1 and Ruminococcus albus 7‐ was studied in the presence or absence of the non-Cellulolytic ruminal Bacteria Selenomonas ruminantium or Streptococcus bovis. Co-cultures were grown under either batch or continuous conditions and populations were estimated using species-specific oligonucleotide probes to 16S rRNA. The three Cellulolytic species co-existed in cellobiose batch co-culture, but inclusion of either Sel. ruminantium or Str. bovis yielded nearly a monoculture of the nonCellulolytic competitor. In cellobiose chemostats, R. albus completely dominated the triculture, but R. flavefaciens became predominant over F. succinogenes and R. albus when Sel. ruminantium was co-inoculated into the chemostats. Similar effects on competition were observed in the presence of Str. bovis at a lower (0<021 h N1 ), but not at a higher (0<045 h N1 ) dilution rate. In cellulose batch co-cultures, R. albus was more abundant than both F. succinogenes and R. flavefaciens, regardless of the presence of the nonCellulolytic species. Co-existence among the three Cellulolytic species was observed in almost all cellulose chemostats, but Sel. ruminantium altered the relative proportions of the Cellulolytic species. R. albus and R. flavefaciens were found to produce inhibitors that suppressed growth of R. flavefaciens and F. succinogenes, respectively. These data indicate that interactions among Cellulolytic Bacteria, while complex, can be modified further by non-Cellulolytic species.
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Competition among three predominant ruminal Cellulolytic Bacteria in the absence or presence of non-Cellulolytic Bacteria
Microbiology, 2001Co-Authors: Junqin Chen, Paul J WeimerAbstract:Competition among three species of ruminal Cellulolytic Bacteria ‐ Fibrobacter succinogenes S85, Ruminococcus flavefaciens FD-1 and Ruminococcus albus 7‐ was studied in the presence or absence of the non-Cellulolytic ruminal Bacteria Selenomonas ruminantium or Streptococcus bovis. Co-cultures were grown under either batch or continuous conditions and populations were estimated using species-specific oligonucleotide probes to 16S rRNA. The three Cellulolytic species co-existed in cellobiose batch co-culture, but inclusion of either Sel. ruminantium or Str. bovis yielded nearly a monoculture of the nonCellulolytic competitor. In cellobiose chemostats, R. albus completely dominated the triculture, but R. flavefaciens became predominant over F. succinogenes and R. albus when Sel. ruminantium was co-inoculated into the chemostats. Similar effects on competition were observed in the presence of Str. bovis at a lower (0
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differential fermentation of cellulose allomorphs by ruminal Cellulolytic Bacteria
Applied and Environmental Microbiology, 1991Co-Authors: Paul J Weimer, A D French, T A CalamariAbstract:In addition to its usual native crystalline form (cellulose I), cellulose can exist in a variety of alternative crystalline forms (allomorphs) which differ in their unit cell dimensions, chain packing schemes, and hydrogen bonding relationships. We prepared, by various chemical treatments, four different alternative allomorphs, along with an amorphous (noncrystalline) cellulose which retained its original molecular weight. We then examined the kinetics of degradation of these materials by two species of ruminal Bacteria and by inocula from two bovine rumens. Ruminococcus flavefaciens FD-1 and Fibrobacter succinogenes S85 were similar to one another in their relative rates of digestion of the different celluloses, which proceeded in the following order: amorphous > IIII > IVI > IIIII > I > II. Unlike F. succinogenes, R. flavefaciens did not degrade cellulose II, even after an incubation of 3 weeks. Comparisons of the structural features of these allomorphs with their digestion kinetics suggest that degradation is enhanced by skewing of adjacent sheets in the microfibril, but is inhibited by intersheet hydrogen bonding and by antiparallelism in adjacent sheets. Mixed microflora from the bovine rumens showed in vitro digestion rates quite different from one another and from those of both of the two pure Bacterial cultures, suggesting that R. flavefaciens and F. succinogenes (purportedly among the most active of the Cellulolytic Bacteria in the rumen) either behave differently in the ruminal ecosystem from the way they do in pure culture or did not play a major role in cellulose digestion in these ruminal samples.
Michael D Flythe - One of the best experts on this subject based on the ideXlab platform.
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biochanin a improves fibre fermentation by Cellulolytic Bacteria
Journal of Applied Microbiology, 2018Co-Authors: B E Harlow, Michael D Flythe, G E AikenAbstract:Aims The objective was to determine the effect of the isoflavone biochanin A (BCA) on rumen Cellulolytic Bacteria and consequent fermentative activity. Methods and Results When bovine microbial rumen cell suspensions (n = 3) were incubated (24 h, 39 °C) with ground hay, Cellulolytic Bacteria proliferated, short chain fatty acids were produced and pH declined. Biochanin A (30 μg mL-1) had no effect on the number of cellulolyic Bacteria or pH, but increased acetate, propionate and total SCFA production. Addition of BCA improved total digestibility when cell suspensions (n = 3) were incubated (48 h, 39 °C) with ground hay, Avicel®, or filter paper. Fibrobacter succinogenes S85, Ruminococcus flavefaciens 8, and R. albus 8 were directly inhibited by BCA. Synergistic antimicrobial activity was observed with BCA and heat killed cultures of Cellulolytic Bacteria, but the effects were species dependent. Conclusions These results indicate that BCA improves fiber degradation by influencing Cellulolytic Bacteria competition and guild composition. Significance and Impact of the Study BCA could serve as a feed additive to improve cellulosis when cattle are consuming high fiber diets. Future research is needed to evaluate the effect of BCA on fiber degradation and utilization in vivo. This article is protected by copyright. All rights reserved.
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diarrhea associated pathogens lactobacilli and Cellulolytic Bacteria in equine feces responses to antibiotic challenge
Veterinary Microbiology, 2013Co-Authors: B E Harlow, Michael D Flythe, Laurie M LawrenceAbstract:Abstract Antibiotics are important to equine medicine, but antibiotic-associated diarrhea (AAD) can lead to poor performance and even mortality. AAD is attributed to disruption of the hindgut microbiota, which permits proliferation of pathogenic microbes. The goal of this study was to evaluate the effects of common antibiotics on Cellulolytic Bacteria, lactobacilli, and AAD-associated pathogens in the feces of healthy horses. Fifteen horses were assigned to three treatment groups (blocked by age and sex): control (no antibiotics), trimethoprim–sulfadiazine (PO), or ceftiofur (IM). Fecal samples ( n = 8 per horse) were taken during dietary adaptation (3 weeks), antibiotic challenge (1 week), and withdrawal (1 week). Bacteria were enumerated by serial dilution and viable count. Cellulolytic Bacteria decreased by >99% during administration of either antibiotic ( P P P P Clostridium perfringens isolates. There was no detectable Clostridium difficile during adaptation or in any control horse. C. difficile increased ( P 4 cfu/g when horses were challenged with antibiotics, and were still detectable 1 week after withdrawal. These results indicate that antibiotics can disrupt the normal gastrointestinal microbiota and allow proliferation of Salmonella spp. and C. difficile .
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Diarrhea-associated pathogens, lactobacilli and Cellulolytic Bacteria in equine feces: responses to antibiotic challenge.
Veterinary microbiology, 2013Co-Authors: Brittany E Harlow, Laurie M Lawrence, Michael D FlytheAbstract:Antibiotics are important to equine medicine, but antibiotic-associated diarrhea (AAD) can lead to poor performance and even mortality. AAD is attributed to disruption of the hindgut microbiota, which permits proliferation of pathogenic microbes. The goal of this study was to evaluate the effects of common antibiotics on Cellulolytic Bacteria, lactobacilli, and AAD-associated pathogens in the feces of healthy horses. Fifteen horses were assigned to three treatment groups (blocked by age and sex): control (no antibiotics), trimethoprim-sulfadiazine (PO), or ceftiofur (IM). Fecal samples (n=8 per horse) were taken during dietary adaptation (3 weeks), antibiotic challenge (1 week), and withdrawal (1 week). Bacteria were enumerated by serial dilution and viable count. Cellulolytic Bacteria decreased by >99% during administration of either antibiotic (P
Kustiawan Tri Pursetyo - One of the best experts on this subject based on the ideXlab platform.
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Isolation and Identification of Cellulolytic Bacteria from Mangrove Soil of Gunung Anyar River Estuary, Surabaya
2020Co-Authors: Kustiawan Tri Pursetyo, Moch. Amin Alamsjah, Rahayu Kusdarwati, Sofie Heliza MaulaniAbstract:Mangroves ecosystem are kind of system arranged by two component, biotic and abiotic which have interaction in mangrove habitat. Biotic components depend on three types such as producer organism, consumer organism and decomposer organism. Mangrove litter is organic material from many decomposition processes, produce an important substance that useful for other organism and coastal productivity especially in the food chain. Mangrove litter could decompose to cellulose material by a microorganism, especially Cellulolytic Bacteria. The soil sample was collected at four stations from Gunung Anyar river estuary Surabaya. The soil sample that has been taking isolated in CMC agar medium, then identified by Gram test, Biochemical test and Inhibition test with a paper disc to observe capability of Cellulolytic Bacteria inhibit the pathogen Bacteria, especially Edwardsiella tarda. Based on Gram stain Test and Biochemical Test find four species of Cellulolytic Bacteria such as Bacillus subtilis, Pseudomonas minute, Micrococcus luteus and Plesiomonas shigelloides. From four species that have been identifying, only Bacillus subtilis and Pseudomonas diminuta that show ability to block pathogenic Bacteria Edwardsiella tarda.
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Kelimpahan Bakteri Selulolitik di Muara Sungai Gunung Anyar Surabaya dan Bancaran Bangkalan [The Total of Cellulolytic Bacteria in Gunung Anyar Surabaya and Bancaran Bangkalan Estuaries ]
Jurnal Ilmiah Perikanan dan Kelautan, 2019Co-Authors: Moch. Amin Alamsjah, Didya Sinatryani, Sudarno Sudarno, Kustiawan Tri PursetyoAbstract:Abstract Most organic materials utilized mangrove detritus such as mangrove leaves fall throughout the year. Organic particles or litter into a place to live for Bacteria, fungi and other microorganisms. One of organic compounds in the soil is cellulose. Deciduous leaves on the ground allows that the cellulose content in the soil is high, it is possible to find cellulose degrading Bacteria in the mangrove ecosystem. Soil sampling conducted in April 2014 located in Gunung Anyar Surabaya estuaries and Bancaran Bangkalan estuaries. After taking the samples, the isolation of Cellulolytic Bacteria and Bacteria calculation were conduct using standard Total Plate Count (TPC). Based on the results of the calculation of total number Bacteria, obtained the highest total number of Cellulolytic Bacteria at station E (Bancaran) of 4.9 x 104 CFU/ml. The highest percentage of Cellulolytic Bacteria obtained at station D (Bancaran) with a percentage of 27.09%. According to the whole calculation of the total number of Bacteria, total number and percentage of Cellulolytic Bacteria, it was found that the area of Bancaran Bangkalan has higher abundance of Cellulolytic Bacteria than Gunung Anyar Surabaya mangrove areas.
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THE TOTAL OF Cellulolytic Bacteria IN GUNUNG ANYAR SURABAYA AND BANCARAN BANGKALAN ESTUARIES
2014Co-Authors: Didya Sinatryani, Moch. Amin Alamsjah, Sudarno, Kustiawan Tri PursetyoAbstract:Most organic materials utilized mangrove detritus such as mangrove leaves fall throughout the year. Organic particles or litter into a place to live for Bacteria, fungi and other microorganisms. One of organic compounds in the soil is cellulose. Deciduous leaves on the ground allows that the cellulose content in the soil is high, it is possible to find cellulose degrading Bacteria in the mangrove ecosystem.Soil sampling conducted in April 2014 located in Gunung Anyar Surabaya estuaries and Bancaran Bangkalan estuaries. After taking the samples, the isolation of Cellulolytic Bacteria and Bacteria calculation were conduct using standard Total Plate Count (TPC).Based on the results of the calculation of total number Bacteria, obtained the highest total number of Cellulolytic Bacteria at station E (Bancaran) of 4.9 x 104 CFU/ml. The highest percentage of Cellulolytic Bacteria obtained at station D (Bancaran) with a percentage of 27.09%. According to the whole calculation of the total number of Bacteria, total number and percentage of Cellulolytic Bacteria, it was found that the area of Bancaran Bangkalan has higher abundance of Cellulolytic Bacteria than Gunung Anyar Surabaya mangrove areas.
Guoping Zhao - One of the best experts on this subject based on the ideXlab platform.
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insight into dominant Cellulolytic Bacteria from two biogas digesters and their glycoside hydrolase genes
PLOS ONE, 2015Co-Authors: Haokui Zhou, Alei Geng, Shengyue Wang, Jun Zhang, Guoping Zhao, L Zhang, Zhihua ZhouAbstract:Diverse Cellulolytic Bacteria are essential for maintaining high lignocellulose degradation ability in biogas digesters. However, little was known about functional genes and gene clusters of dominant Cellulolytic Bacteria in biogas digesters. This is the foundation to understand lignocellulose degradation mechanisms of biogas digesters and apply these gene resource for optimizing biofuel production. A combination of metagenomic and 16S rRNA gene clone library methods was used to investigate the dominant Cellulolytic Bacteria and their glycoside hydrolase (GH) genes in two biogas digesters. The 16S rRNA gene analysis revealed that the dominant Cellulolytic Bacteria were strains closely related to Clostridium straminisolvens and an uncultured Cellulolytic bacterium designated BG-1. To recover GH genes from Cellulolytic Bacteria in general, and BG-1 in particular, a refined assembly approach developed in this study was used to assemble GH genes from metagenomic reads; 163 GH-containing contigs ≥ 1 kb in length were obtained. Six recovered GH5 genes that were expressed in E. coli demonstrated multiple lignocellulase activities and one had high mannanase activity (1255 U/mg). Eleven fosmid clones harboring the recovered GH-containing contigs were sequenced and assembled into 10 fosmid contigs. The composition of GH genes in the 163 assembled metagenomic contigs and 10 fosmid contigs indicated that diverse GHs and lignocellulose degradation mechanisms were present in the biogas digesters. In particular, a small portion of BG-1 genome information was recovered by PhyloPythiaS analysis. The lignocellulase gene clusters in BG-1 suggested that it might use a possible novel lignocellulose degradation mechanism to efficiently degrade lignocellulose. Dominant Cellulolytic Bacteria of biogas digester possess diverse GH genes, not only in sequences but also in their functions, which may be applied for production of biofuel in the future.
James B Russell - One of the best experts on this subject based on the ideXlab platform.
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quantitative analysis of cellulose degradation and growth of Cellulolytic Bacteria in the rumen
FEMS Microbiology Ecology, 2009Co-Authors: James B Russell, R E Muck, Paul J WeimerAbstract:Ruminant animals digest cellulose via a symbiotic relationship with ruminal microorganisms. Because feedstuffs only remain in the rumen for a short time, the rate of cellulose digestion must be very rapid. This speed is facilitated by rumination, a process that returns food to the mouth to be rechewed. By decreasing particle size, the cellulose surface area can be increased by up to 106-fold. The amount of cellulose digested is then a function of two competing rates, namely the digestion rate (Kd) and the rate of passage of solids from the rumen (Kp). Estimation of Bacterial growth on cellulose is complicated by several factors: (1) energy must be expended for maintenance and growth of the cells, (2) only adherent cells are capable of degrading cellulose and (3) adherent cells can provide nonadherent cells with cellodextrins. Additionally, when ruminants are fed large amounts of cereal grain along with fiber, ruminal pH can decrease to a point where Cellulolytic Bacteria no longer grow. A dynamic model based on stella® software is presented. This model evaluates all of the major aspects of ruminal cellulose degradation: (1) ingestion, digestion and passage of feed particles, (2) maintenance and growth of Cellulolytic Bacteria and (3) pH effects.
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why are ruminal Cellulolytic Bacteria unable to digest cellulose at low ph
Journal of Dairy Science, 1996Co-Authors: James B Russell, David WilsonAbstract:Ruminant animals depend on Cellulolytic ruminal Bacteria to digest cellulose, but these Bacteria cannot resist the low ruminal pH that modern feeding practices can create. Because the Cellulolytic Bacteria cannot grow on cellobiose at low pH, pH sensitivity is a general aspect of growth and not just a limitation of the cellulases per se. Acid-resistant ruminal Bacteria have evolved the capacity to let their intracellular pH decrease, maintain a small pH gradient across the cell membrane, and prevent an intracellular accumulation of VFA anions. Cellulolytic Bacteria cannot grow with a low intracellular pH, and an increase in pH gradient leads to anion toxicity. Prevotella ruminicola cannot digest native cellulose, but it grows at low pH and degrades the cellulose derivative, carboxymethylcellulose. The Prevotella ruminicola carboxymethylcellulase cannot bind to cellulose, but a recombinant enzyme having the Prevotella ruminicola catalytic domain and a binding domain from Thermomonspora fusca was able to bind and had cellulase activity that was at least 10-fold higher. Based on these results, gene reconstruction offers a means of converting Prevotella ruminicola into a ruminal bacterium that can digest cellulose at low pH.