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Liu J, Shi J, Gao J, Shi R, Zhu J, Jensen MS, Li C, Yang J, Zhao S, Sun A, Sun D, Zhang Y, Liu C, Liu W. Functional studies on tandem carbohydrate-binding modules of a multimodular enzyme possessing two catalytic domains. Appl Environ Microbiol 2024; 90:e0088824. [PMID: 38940565 PMCID: PMC11267928 DOI: 10.1128/aem.00888-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2024] [Accepted: 06/09/2024] [Indexed: 06/29/2024] Open
Abstract
Although functional studies on carbohydrate-binding module (CBM) have been carried out extensively, the role of tandem CBMs in the enzyme containing multiple catalytic domains (CDs) is unclear. Here, we identified a multidomain enzyme (Lc25986) with a novel modular structure from lignocellulolytic bacterial consortium. It consists of a mannanase domain, two CBM65 domains (LcCBM65-1/LcCBM65-2), and an esterase domain. To investigate CBM function and domain interactions, full-length Lc25986 and its variants were constructed and used for enzymatic activity, binding, and bioinformatic analyses. The results showed that LcCBM65-1 and LcCBM65-2 both bind mannan and xyloglucan but not cellulose or β-1,3-1,4-glucan, which differs from the ligand specificity of reported CBM65s. Compared to LcCBM65-2, LcCBM65-1 showed a stronger ligand affinity and a preference for acetylation sites. Both CBM65s stimulated the enzymatic activities of their respective neighboring CDs against acetylated mannan, but did not contribute to the activities of the distal CDs. The time course of mannan hydrolysis indicated that the full-length Lc25986 was more effective in the complete degradation of mixed acetyl/non-acetyl substrates than the mixture of single-CD mutants. When acting on complex substrates, LcCBM65-1 not only improved the enzymatic activity of the mannanase domain, but also directed the esterase domain to the acetylated polysaccharides. LcCBM65-2 adopted a low affinity to reduce interference with the catalysis of the mannanase domain. These results demonstrate the importance of CBMs for the synergism between the two CDs of a multidomain enzyme and suggest that they contribute to the adequate degradation of complex substrates such as plant cell walls. IMPORTANCE Lignocellulolytic enzymes, particularly those of bacterial origin, often harbor multiple carbohydrate-binding modules (CBMs). However, the function of CBM multivalency remains poorly understood. This is especially true for enzymes that contain more than one catalytic domain (CD), as the interactions between CDs, CBMs, and CDs and CBMs can be complex. Our research demonstrates that homogeneous CBMs can have distinct functions in a multimodular enzyme. The tandem CBMs coordinate the CDs in catalytic conflict through their differences in binding affinity, ligand preference, and arrangement within the full-length enzyme. Additionally, although the synergism between mannanase and esterase is widely acknowledged, our study highlights the benefits of integrating the two enzymes into a single entity for the degradation of complex substrates. In summary, these findings enhance our understanding of the intra-synergism of a multimodular enzyme and emphasize the significance of multiple CBMs in this context.
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Affiliation(s)
- Jiawen Liu
- School of Life Science, Jiangsu Normal University, Xuzhou, Jiangsu, China
| | - Jiani Shi
- School of Life Science, Jiangsu Normal University, Xuzhou, Jiangsu, China
| | - Jiahui Gao
- School of Life Science, Jiangsu Normal University, Xuzhou, Jiangsu, China
| | - Rui Shi
- School of Life Science, Jiangsu Normal University, Xuzhou, Jiangsu, China
| | - Jingrong Zhu
- School of Life Science, Jiangsu Normal University, Xuzhou, Jiangsu, China
| | - Marcus Sepo Jensen
- School of Life Science, Jiangsu Normal University, Xuzhou, Jiangsu, China
| | - Chenchen Li
- School of Life Science, Jiangsu Normal University, Xuzhou, Jiangsu, China
| | - Jing Yang
- School of Life Science, Jiangsu Normal University, Xuzhou, Jiangsu, China
| | - Siyi Zhao
- School of Life Science, Jiangsu Normal University, Xuzhou, Jiangsu, China
| | - Aofei Sun
- School of Life Science, Jiangsu Normal University, Xuzhou, Jiangsu, China
| | - Di Sun
- School of Life Science, Jiangsu Normal University, Xuzhou, Jiangsu, China
| | - Ying Zhang
- School of Life Science, Beijing Institute of Technology, Beijing, China
| | - Cong Liu
- School of Life Science, Jiangsu Normal University, Xuzhou, Jiangsu, China
| | - Weijie Liu
- School of Life Science, Jiangsu Normal University, Xuzhou, Jiangsu, China
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Wang Y, Mairinger W, Raj SJ, Yakubu H, Siesel C, Green J, Durry S, Joseph G, Rahman M, Amin N, Hassan MZ, Wicken J, Dourng D, Larbi E, Adomako LAB, Senayah AK, Doe B, Buamah R, Tetteh-Nortey JNN, Kang G, Karthikeyan A, Roy S, Brown J, Muneme B, Sene SO, Tuffuor B, Mugambe RK, Bateganya NL, Surridge T, Ndashe GM, Ndashe K, Ban R, Schrecongost A, Moe CL. Quantitative assessment of exposure to fecal contamination in urban environment across nine cities in low-income and lower-middle-income countries and a city in the United States. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 763:143007. [PMID: 34718001 DOI: 10.1016/j.scitotenv.2020.143007] [Citation(s) in RCA: 48] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2020] [Revised: 10/08/2020] [Accepted: 10/08/2020] [Indexed: 05/23/2023]
Abstract
BACKGROUND During 2014 to 2019, the SaniPath Exposure Assessment Tool, a standardized set of methods to evaluate risk of exposure to fecal contamination in the urban environment through multiple exposure pathways, was deployed in 45 neighborhoods in ten cities, including Accra and Kumasi, Ghana; Vellore, India; Maputo, Mozambique; Siem Reap, Cambodia; Atlanta, United States; Dhaka, Bangladesh; Lusaka, Zambia; Kampala, Uganda; Dakar, Senegal. OBJECTIVE Assess and compare risk of exposure to fecal contamination via multiple pathways in ten cities. METHODS In total, 4053 environmental samples, 4586 household surveys, 128 community surveys, and 124 school surveys were collected. E. coli concentrations were measured in environmental samples as an indicator of fecal contamination magnitude. Bayesian methods were used to estimate the distributions of fecal contamination concentration and contact frequency. Exposure to fecal contamination was estimated by the Monte Carlo method. The contamination levels of ten environmental compartments, frequency of contact with those compartments for adults and children, and estimated exposure to fecal contamination through any of the surveyed environmental pathways were compared across cities and neighborhoods. RESULTS Distribution of fecal contamination in the environment and human contact behavior varied by city. Universally, food pathways were the most common dominant route of exposure to fecal contamination across cities in low-income and lower-middle-income countries. Risks of fecal exposure via water pathways, such as open drains, flood water, and municipal drinking water, were site-specific and often limited to smaller geographic areas (i.e., neighborhoods) instead of larger areas (i.e., cities). CONCLUSIONS Knowledge of the relative contribution to fecal exposure from multiple pathways, and the environmental contamination level and frequency of contact for those "dominant pathways" could provide guidance for Water, Sanitation, and Hygiene (WASH) programming and investments and enable local governments and municipalities to improve intervention strategies to reduce the risk of exposure to fecal contamination.
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Affiliation(s)
- Yuke Wang
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA.
| | - Wolfgang Mairinger
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Suraja J Raj
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Habib Yakubu
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Casey Siesel
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Jamie Green
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Sarah Durry
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - George Joseph
- Water Global Practice, The World Bank, Washington, DC, USA
| | - Mahbubur Rahman
- Environmental Interventions Unit, Infectious Disease Division, International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka, Bangladesh
| | - Nuhu Amin
- Environmental Interventions Unit, Infectious Disease Division, International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka, Bangladesh
| | | | | | | | - Eugene Larbi
- Training Research and Networking for Development (TREND), Accra, Ghana
| | | | | | - Benjamin Doe
- Training Research and Networking for Development (TREND), Accra, Ghana
| | - Richard Buamah
- Department of Civil Engineering, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | | | - Gagandeep Kang
- Wellcome Research Laboratory, Christian Medical College, Vellore, India
| | - Arun Karthikeyan
- Wellcome Research Laboratory, Christian Medical College, Vellore, India
| | - Sheela Roy
- Wellcome Research Laboratory, Christian Medical College, Vellore, India
| | - Joe Brown
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - Bacelar Muneme
- Water Supply and Mapping, WE Consult, Maputo, Mozambique
| | - Seydina O Sene
- Initiative Prospective Agricole et Rurale (IPAR), Dakar, Senegal
| | - Benedict Tuffuor
- Training Research and Networking for Development (TREND), Accra, Ghana
| | - Richard K Mugambe
- Department of Disease Control and Environmental Health, Makerere University School of Public Health, Kampala, Uganda
| | - Najib Lukooya Bateganya
- Department of Environment and Public Health, Kampala Capital City Authority, Kampala, Uganda
| | - Trevor Surridge
- Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ) GmbH, Lusaka, Zambia
| | | | - Kunda Ndashe
- Department of Environmental Health, Faculty of Health Science, Lusaka Apex Medical University, Lusaka, Zambia
| | - Radu Ban
- Bill & Melinda Gates Foundation, Seattle, WA, USA
| | | | - Christine L Moe
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
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Sato Y, Takebe H, Tominaga K, Oishi K, Kumagai H, Yoshida T, Hirooka H. Taxonomic and functional characterization of the rumen microbiome of Japanese Black cattle revealed by 16S rRNA gene amplicon and metagenome shotgun sequencing. FEMS Microbiol Ecol 2021; 97:6447535. [PMID: 34864967 DOI: 10.1093/femsec/fiab152] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 11/28/2021] [Indexed: 01/04/2023] Open
Abstract
This study aimed to determine the taxonomic and functional characteristics of the Japanese Black (JB) steer rumen microbiome. The rumen microbiomes of six JB steers (age 14.7 ± 1.44 months) and six JB sires × Holstein dams crossbred (F1) steers (age 11.1 ± 0.39 months), fed the same diet, were evaluated. Based on 16S rRNA gene sequencing, the beta diversity revealed differences in microbial community structures between the JB and F1 rumen. Shotgun sequencing showed that Fibrobacter succinogenes and two Ruminococcus spp., which are related to cellulose degradation were relatively more abundant in the JB steer rumen than in the F1 rumen. Furthermore, the 16S rRNA gene copy number of F. succinogenes was significantly higher in the JB steer rumen than in the F1 rumen according to quantitative real-time polymerase chain reaction analysis. Genes encoding the enzymes that accelerate cellulose degradation and those associated with hemicellulose degradation were enriched in the JB steer rumen. Although Prevotella spp. were predominant both in the JB and F1 rumen, the genes encoding carbohydrate-active enzymes of Prevotella spp. may differ between JB and F1.
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Affiliation(s)
- Yoshiaki Sato
- Laboratory of Animal Husbandry Resources, Division of Applied Biosciences, Graduate School of Agriculture, Kyoto University, Kitashirakawa Oiwake, Kyoto 606-8502, Japan
| | - Hiroaki Takebe
- Laboratory of Marine Microbiology, Division of Applied Biosciences, Graduate School of Agriculture, Kyoto University, Kitashirakawa Oiwake, Kyoto 606-8502, Japan
| | - Kento Tominaga
- Laboratory of Marine Microbiology, Division of Applied Biosciences, Graduate School of Agriculture, Kyoto University, Kitashirakawa Oiwake, Kyoto 606-8502, Japan
| | - Kazato Oishi
- Laboratory of Animal Husbandry Resources, Division of Applied Biosciences, Graduate School of Agriculture, Kyoto University, Kitashirakawa Oiwake, Kyoto 606-8502, Japan
| | - Hajime Kumagai
- Laboratory of Animal Husbandry Resources, Division of Applied Biosciences, Graduate School of Agriculture, Kyoto University, Kitashirakawa Oiwake, Kyoto 606-8502, Japan
| | - Takashi Yoshida
- Laboratory of Marine Microbiology, Division of Applied Biosciences, Graduate School of Agriculture, Kyoto University, Kitashirakawa Oiwake, Kyoto 606-8502, Japan
| | - Hiroyuki Hirooka
- Laboratory of Animal Husbandry Resources, Division of Applied Biosciences, Graduate School of Agriculture, Kyoto University, Kitashirakawa Oiwake, Kyoto 606-8502, Japan
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A new landscape of rabbit gut microbiota shaped by the infection of precocious parasites of Eimeria intestinalis. Vet Parasitol 2021; 300:109579. [PMID: 34784535 DOI: 10.1016/j.vetpar.2021.109579] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 09/14/2021] [Accepted: 09/16/2021] [Indexed: 12/12/2022]
Abstract
Rabbit intestinal coccidiosis is caused by one or several Eimeria species, which cause intestinal damage and secondary bacterial infection. However, the impact of Eimeria infection on gut microbiota is much unknown. To evaluate the influence, we detected the feces flora of SPF rabbits infected with the 1 × 104 oocysts of E. intestinalis wild type (WT) and a precocious line (EIP8), a highly pathogenic species, by 16S rRNA sequencing. The microbiota of newly weaned rabbits post vaccination with low doses of EIP8 oocysts was also detected. In SPF rabbits, while Ruminococcaceae, Lachnospiraceae, and Bacteroidaceae were dominant families in all groups, EIP8 infection induced less changes in beta-diversity. In EIP8-infected rabbits, the intestinal flora whose abundance changed post infection accounted for less than 5.23 % of the entire flora. In comparison, it accounted for 27.18 % in WT group on d14 PI, while it was more than 20 % in diclazuril control group on d7 or d10 PI. The amount of fecal IgA and the abundance of IgA-production-related bacteria were similar in either EIP8 or WT infected rabbits. In the newly weaned rabbits, vaccination with EIP8 provided sufficient protection against challenge with WT parasites, as the body weight gain of vaccinated rabbits was similar to that of untreated animals, as well as more than 80 % reduction of oocyst output was detected when compared with unimmunized and challenged animals. Moreover, the vaccination had no significant impact on rabbit microbiota. Together, our findings suggested that the precocious line of E. intestinalis, compared with WT, induced a new fecal microbiota biodiversity in rabbits.
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Gomez A, Sharma AK, Grev A, Sheaffer C, Martinson K. The Horse Gut Microbiome Responds in a Highly Individualized Manner to Forage Lignification. J Equine Vet Sci 2020; 96:103306. [PMID: 33349409 DOI: 10.1016/j.jevs.2020.103306] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 10/13/2020] [Accepted: 10/13/2020] [Indexed: 12/30/2022]
Abstract
Although contributions of the equine gut microbiome to forage utilization are well recognized, the impact of alfalfa (Medicago sativa L.) lignification on the equine gut microbiome remains unknown; thus, we characterized microbial communities in the equine gut when feeding reduced lignin (RL) and conventional (CON) alfalfa hays to adult stock-type horses. Dietary treatments were fed to six horses in a crossover study. Experimental periods consisted of a 9-day dietary adaptation phase followed by a 5-day total fecal collection phase, during which horses were housed in individual box stalls and manure was removed on a continuous 24-hour basis. At 12-hour intervals, manure was mixed, frozen, and processed for V4, 16S rRNA amplicon MiSeq sequencing. Reduced lignin alfalfa did not shift microbiome composition equally across all horses; however, each subject's microbiome responded to hay lignin content in an individualized manner, mostly, in terms of beta diversity. Amplicon sequence variants affiliated to Akkermansia, Fibrobacter succinogenes, Treponema, and Paludibacter fluctuated significantly when RL alfalfa was fed, with abundance patterns unique to each horse. Horse-specific associations between individual gut microbiome traits and characteristics of the digested CON or RL alfalfa were also observed, mainly in regards to dry matter digestibility and mean fecal particle size. These results indicate that the horse gut microbiome responds in an individualized manner to changes in the amount of acid detergent lignin in alfalfa hay, potentially impacting several feed digestibility characteristics. The implications of these horse-specific responses to hay lignification, for metabolic health and performance, remain to be elucidated.
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Affiliation(s)
- Andres Gomez
- Department of Animal Science, University of Minnesota, St. Paul, MN.
| | | | - Amanda Grev
- Department of Animal Science, University of Minnesota, St. Paul, MN
| | - Craig Sheaffer
- Department of Agronomy and Plant Genetics, University of Minnesota, St. Paul, MN
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6
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Kozaki R, Miyake H. Enzymatic and molecular characterization of an endoglucanase E from Clostridium cellulovorans 743B. J Biosci Bioeng 2019; 128:398-404. [DOI: 10.1016/j.jbiosc.2019.03.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Revised: 03/08/2019] [Accepted: 03/15/2019] [Indexed: 10/27/2022]
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Hwangbo M, Tran JL, Chu KH. Effective one-step saccharification of lignocellulosic biomass using magnetite-biocatalysts containing saccharifying enzymes. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 647:806-813. [PMID: 30096670 DOI: 10.1016/j.scitotenv.2018.08.066] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 08/03/2018] [Accepted: 08/04/2018] [Indexed: 06/08/2023]
Abstract
Lignocellulosic biomass, packed with sugars, is one of the most available renewable resources for biofuels and bioproducts production. To release the sugars for the production, enzymatic hydrolysis (saccharification) of pretreated lignocellulosic biomass are required. However, the saccharification process is costly, inefficient, and requires multi-step operations. This is in part due to the high cost and the limited selection of commercial enzymes which commonly have different optimal pH and temperatures. Here we reported a one-step saccharification of pretreated lignocellulosic biomass using immobilized biocatalysts containing five different saccharifying enzymes (SEs) with a similar optimum pH and temperature. The five SEs - endo-1,4-β-d-glucanase (an endoglucanase, eglS), cellobiohydrolase (an exoglucanase, cbhA), and β-glucosidase (bglH), endo-1,4-β-xylanase (an endoxylanase, xynC) and β-xylosidase (bxlB) - were successfully expressed and produced by E. coli BL21. Better saccharification of pretreated corn husks was observed when using the five crude SE enzymes than those using two commonly used SEs, endo-1,4-β-d-glucanase and β-glucosidase. The five SEs were cross-linked in the absence or the presence of magnetic nanoparticles (hereafter referred as SE-CLEAs and M-SE-CLEAs, respectively). By using SE-CLEAs, the highest amount of reduced sugar (250 mg/g biomass) was measured. The activity of immobilized SEs is better than free crude SEs. The M-SE-CLEAs can be reused at least 3 times for effective saccharification of pretreated lignocellulosic biomass.
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Affiliation(s)
- Myung Hwangbo
- Zachry Department of Civil Engineering, Texas A&M University, College Station, TX 77843-3136, USA
| | - Janessa L Tran
- Zachry Department of Civil Engineering, Texas A&M University, College Station, TX 77843-3136, USA
| | - Kung-Hui Chu
- Zachry Department of Civil Engineering, Texas A&M University, College Station, TX 77843-3136, USA.
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8
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The Ruminococci: key symbionts of the gut ecosystem. J Microbiol 2018; 56:199-208. [PMID: 29492877 DOI: 10.1007/s12275-018-8024-4] [Citation(s) in RCA: 187] [Impact Index Per Article: 31.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 02/05/2018] [Accepted: 02/12/2018] [Indexed: 12/22/2022]
Abstract
Mammalian gut microbial communities form intricate mutualisms with their hosts, which have profound implications on overall health. One group of important gut microbial mutualists are bacteria in the genus Ruminococcus, which serve to degrade and convert complex polysaccharides into a variety of nutrients for their hosts. Isolated decades ago from the bovine rumen, ruminococci have since been cultured from other ruminant and non-ruminant sources, and next-generation sequencing has further shown their distribution to be widespread in a diversity of animal hosts. While most ruminococci that have been studied are those capable of degrading cellulose, much less is known about non-cellulolytic, nonruminant-associated species, such as those found in humans. Furthermore, a mechanistic understanding of the role of Ruminococcus spp. in their respective hosts is still a work in progress. This review highlights the broad work done on species within the genus Ruminococcus with respect to their physiology, phylogenetic relatedness, and their potential impact on host health.
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9
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Devendran S, Abdel-Hamid AM, Evans AF, Iakiviak M, Kwon IH, Mackie RI, Cann I. Multiple cellobiohydrolases and cellobiose phosphorylases cooperate in the ruminal bacterium Ruminococcus albus 8 to degrade cellooligosaccharides. Sci Rep 2016; 6:35342. [PMID: 27748409 PMCID: PMC5066209 DOI: 10.1038/srep35342] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Accepted: 09/28/2016] [Indexed: 12/01/2022] Open
Abstract
Digestion of plant cell wall polysaccharides is important in energy capture in the gastrointestinal tract of many herbivorous and omnivorous mammals, including humans and ruminants. The members of the genus Ruminococcus are found in both the ruminant and human gastrointestinal tract, where they show versatility in degrading both hemicellulose and cellulose. The available genome sequence of Ruminococcus albus 8, a common inhabitant of the cow rumen, alludes to a bacterium well-endowed with genes that target degradation of various plant cell wall components. The mechanisms by which R. albus 8 employs to degrade these recalcitrant materials are, however, not clearly understood. In this report, we demonstrate that R. albus 8 elaborates multiple cellobiohydrolases with multi-modular architectures that overall enhance the catalytic activity and versatility of the enzymes. Furthermore, our analyses show that two cellobiose phosphorylases encoded by R. albus 8 can function synergistically with a cognate cellobiohydrolase and endoglucanase to completely release, from a cellulosic substrate, glucose which can then be fermented by the bacterium for production of energy and cellular building blocks. We further use transcriptomic analysis to confirm the over-expression of the biochemically characterized enzymes during growth of the bacterium on cellulosic substrates compared to cellobiose.
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Affiliation(s)
- Saravanan Devendran
- Energy Biosciences Institute, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.,Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - Ahmed M Abdel-Hamid
- Energy Biosciences Institute, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.,Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - Anton F Evans
- Energy Biosciences Institute, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.,Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.,School of Molecular and Cellular Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - Michael Iakiviak
- Department of Animal Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - In Hyuk Kwon
- Department of Animal Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - Roderick I Mackie
- Energy Biosciences Institute, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.,Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.,Department of Animal Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - Isaac Cann
- Energy Biosciences Institute, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.,Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.,School of Molecular and Cellular Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.,Department of Animal Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.,Department of Microbiology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
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