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Novak JK, Gardner JG. Current models in bacterial hemicellulase-encoding gene regulation. Appl Microbiol Biotechnol 2024; 108:39. [PMID: 38175245 PMCID: PMC10766802 DOI: 10.1007/s00253-023-12977-4] [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: 12/06/2023] [Revised: 12/06/2023] [Accepted: 12/07/2023] [Indexed: 01/05/2024]
Abstract
The discovery and characterization of bacterial carbohydrate-active enzymes is a fundamental component of biotechnology innovation, particularly for renewable fuels and chemicals; however, these studies have increasingly transitioned to exploring the complex regulation required for recalcitrant polysaccharide utilization. This pivot is largely due to the current need to engineer and optimize enzymes for maximal degradation in industrial or biomedical applications. Given the structural simplicity of a single cellulose polymer, and the relatively few enzyme classes required for complete bioconversion, the regulation of cellulases in bacteria has been thoroughly discussed in the literature. However, the diversity of hemicelluloses found in plant biomass and the multitude of carbohydrate-active enzymes required for their deconstruction has resulted in a less comprehensive understanding of bacterial hemicellulase-encoding gene regulation. Here we review the mechanisms of this process and common themes found in the transcriptomic response during plant biomass utilization. By comparing regulatory systems from both Gram-negative and Gram-positive bacteria, as well as drawing parallels to cellulase regulation, our goals are to highlight the shared and distinct features of bacterial hemicellulase-encoding gene regulation and provide a set of guiding questions to improve our understanding of bacterial lignocellulose utilization. KEY POINTS: • Canonical regulatory mechanisms for bacterial hemicellulase-encoding gene expression include hybrid two-component systems (HTCS), extracytoplasmic function (ECF)-σ/anti-σ systems, and carbon catabolite repression (CCR). • Current transcriptomic approaches are increasingly being used to identify hemicellulase-encoding gene regulatory patterns coupled with computational predictions for transcriptional regulators. • Future work should emphasize genetic approaches to improve systems biology tools available for model bacterial systems and emerging microbes with biotechnology potential. Specifically, optimization of Gram-positive systems will require integration of degradative and fermentative capabilities, while optimization of Gram-negative systems will require bolstering the potency of lignocellulolytic capabilities.
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Affiliation(s)
- Jessica K Novak
- Department of Biological Sciences, University of Maryland - Baltimore County, Baltimore, MD, USA
| | - Jeffrey G Gardner
- Department of Biological Sciences, University of Maryland - Baltimore County, Baltimore, MD, USA.
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Wang Y, Qian J, Shi T, Wang Y, Ding Q, Ye C. Application of extremophile cell factories in industrial biotechnology. Enzyme Microb Technol 2024; 175:110407. [PMID: 38341913 DOI: 10.1016/j.enzmictec.2024.110407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 01/24/2024] [Accepted: 01/26/2024] [Indexed: 02/13/2024]
Abstract
Due to the extreme living conditions, extremophiles have unique characteristics in morphology, structure, physiology, biochemistry, molecular evolution mechanism and so on. Extremophiles have superior growth and synthesis capabilities under harsh conditions compared to conventional microorganisms, allowing for unsterilized fermentation processes and thus better performance in low-cost production. In recent years, due to the development and optimization of molecular biology, synthetic biology and fermentation technology, the identification and screening technology of extremophiles has been greatly improved. In this review, we summarize techniques for the identification and screening of extremophiles and review their applications in industrial biotechnology in recent years. In addition, the facts and perspectives gathered in this review suggest that next-generation industrial biotechnology (NGIBs) based on engineered extremophiles holds the promise of simplifying biofuturing processes, establishing open, non-sterilized continuous fermentation production systems, and utilizing low-cost substrates to make NGIBs attractive and cost-effective bioprocessing technologies for sustainable manufacturing.
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Affiliation(s)
- Yuzhou Wang
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing 210023, PR China
| | - Jinyi Qian
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing 210023, PR China
| | - Tianqiong Shi
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing 210023, PR China
| | - Yuetong Wang
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing 210023, PR China
| | - Qiang Ding
- School of Life Sciences, Anhui University, Hefei 230601, PR China.
| | - Chao Ye
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing 210023, PR China; Ministry of Education Key Laboratory of NSLSCS.
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Huang S, Xue Y, Zhou C, Ma Y. An efficient
CRISPR
/Cas9‐based genome editing system for alkaliphilic
Bacillus
sp.
N16
‐5 and application in engineering xylose utilization for
D
‐lactic acid production. Microb Biotechnol 2022; 15:2730-2743. [DOI: 10.1111/1751-7915.14131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 07/27/2022] [Accepted: 07/29/2022] [Indexed: 11/28/2022] Open
Affiliation(s)
- Shiyong Huang
- State Key Laboratory of Microbial Resources, Institute of Microbiology Chinese Academy of Sciences Beijing China
- University of Chinese Academy of Sciences Beijing China
| | - Yanfen Xue
- State Key Laboratory of Microbial Resources, Institute of Microbiology Chinese Academy of Sciences Beijing China
| | - Cheng Zhou
- State Key Laboratory of Microbial Resources, Institute of Microbiology Chinese Academy of Sciences Beijing China
| | - Yanhe Ma
- State Key Laboratory of Microbial Resources, Institute of Microbiology Chinese Academy of Sciences Beijing China
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Song Y, Sun W, Fan Y, Xue Y, Liu D, Ma C, Liu W, Mosher W, Luo X, Li Z, Ma W, Zhang T. Galactomannan Degrading Enzymes from the Mannan Utilization Gene Cluster of Alkaliphilic Bacillus sp. N16-5 and Their Synergy on Galactomannan Degradation. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2018; 66:11055-11063. [PMID: 30351049 DOI: 10.1021/acs.jafc.8b03878] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Two glycoside hydrolases encoded by the mannan utilization gene cluster of alkaliphilic Bacillus sp. N16-5 were studied. The recombinant Gal27A (rGal27A) hydrolyzed both galactomannans and oligo-galactomannans to release galactose, while the recombinant Man113A (rMan113A) showed poor activity toward galactomannans, but it hydrolyzed manno-oligosaccharides to release mannose and mannobiose. rGal27A showed synergistic interactions with rMan113A and recombinant β-mannanase ManA (rManA), which is also from Bacillus sp. N16-5, in galactomannan degradation. The synergy degree of rGal27A and rManA on hydrolysis of locust bean gum and guar gum was 1.13 and 2.21, respectively, and that of rGal27A and rMan113A reached 2.00 and 2.68. The main products of galactomannan hydrolyzed by rGal27A and rManA simultaneously were galactose, mannose, mannobiose, and mannotriose, while those of galactomannan hydrolyzed by rGal27A and rMan113A were galactose and mannose. The yields of mannose, mannobiose, and mannotriose dramatically increased compared with the hydrolysis in the presence of rManA or rMan113A alone.
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Affiliation(s)
- Yajian Song
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Industrial Fermentation Microbiology of Ministry of Education & Tianjin Key Laboratory of Industrial Microbiology, College of Biotechnology , Tianjin University of Science and Technology , Tianjin 300457 , China
| | - Wenyuan Sun
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Industrial Fermentation Microbiology of Ministry of Education & Tianjin Key Laboratory of Industrial Microbiology, College of Biotechnology , Tianjin University of Science and Technology , Tianjin 300457 , China
| | - Yanli Fan
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Industrial Fermentation Microbiology of Ministry of Education & Tianjin Key Laboratory of Industrial Microbiology, College of Biotechnology , Tianjin University of Science and Technology , Tianjin 300457 , China
| | - Yanfen Xue
- State Key Laboratory of Microbial Resources, Institute of Microbiology , Chinese Academy of Sciences , Beijing 100101 , China
| | - Duoduo Liu
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Industrial Fermentation Microbiology of Ministry of Education & Tianjin Key Laboratory of Industrial Microbiology, College of Biotechnology , Tianjin University of Science and Technology , Tianjin 300457 , China
| | - Cuiping Ma
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Industrial Fermentation Microbiology of Ministry of Education & Tianjin Key Laboratory of Industrial Microbiology, College of Biotechnology , Tianjin University of Science and Technology , Tianjin 300457 , China
| | - Wenting Liu
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Industrial Fermentation Microbiology of Ministry of Education & Tianjin Key Laboratory of Industrial Microbiology, College of Biotechnology , Tianjin University of Science and Technology , Tianjin 300457 , China
- Tianjin Institute of Industrial Biotechnology , Chinese Academy of Sciences , Tianjin 300308 , China
| | - Wesley Mosher
- Department of Food Science and Nutrition , University of Minnesota , St. Paul , Minnesota 55108 , United States
| | - Xuegang Luo
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Industrial Fermentation Microbiology of Ministry of Education & Tianjin Key Laboratory of Industrial Microbiology, College of Biotechnology , Tianjin University of Science and Technology , Tianjin 300457 , China
| | - Zhongyuan Li
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Industrial Fermentation Microbiology of Ministry of Education & Tianjin Key Laboratory of Industrial Microbiology, College of Biotechnology , Tianjin University of Science and Technology , Tianjin 300457 , China
| | - Wenjian Ma
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Industrial Fermentation Microbiology of Ministry of Education & Tianjin Key Laboratory of Industrial Microbiology, College of Biotechnology , Tianjin University of Science and Technology , Tianjin 300457 , China
| | - Tongcun Zhang
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Industrial Fermentation Microbiology of Ministry of Education & Tianjin Key Laboratory of Industrial Microbiology, College of Biotechnology , Tianjin University of Science and Technology , Tianjin 300457 , China
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5
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Song Y, Liu D, Liu M, Yang H, Fan Y, Sun W, Xue Y, Zhang T, Ma Y. Transcriptional regulation of the mannan utilization genes in the alkaliphilic Bacillus sp. N16-5. FEMS Microbiol Lett 2018; 365:4816728. [DOI: 10.1093/femsle/fnx280] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Accepted: 01/17/2018] [Indexed: 11/13/2022] Open
Affiliation(s)
- Yajian Song
- Key Laboratory of Industrial Fermentation Microbiology of Ministry of Education, Tianjin Key Laboratory of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Duoduo Liu
- Key Laboratory of Industrial Fermentation Microbiology of Ministry of Education, Tianjin Key Laboratory of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Mengya Liu
- Key Laboratory of Industrial Fermentation Microbiology of Ministry of Education, Tianjin Key Laboratory of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Haixu Yang
- Key Laboratory of Industrial Fermentation Microbiology of Ministry of Education, Tianjin Key Laboratory of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Yanli Fan
- Key Laboratory of Industrial Fermentation Microbiology of Ministry of Education, Tianjin Key Laboratory of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Wenyuan Sun
- Key Laboratory of Industrial Fermentation Microbiology of Ministry of Education, Tianjin Key Laboratory of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Yanfen Xue
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Tongcun Zhang
- Key Laboratory of Industrial Fermentation Microbiology of Ministry of Education, Tianjin Key Laboratory of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Yanhe Ma
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
- National Engineering Laboratory for Industrial Enzymes, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
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Ferreira MJ, Mendes AL, de Sá-Nogueira I. The MsmX ATPase plays a crucial role in pectin mobilization by Bacillus subtilis. PLoS One 2017; 12:e0189483. [PMID: 29240795 PMCID: PMC5730181 DOI: 10.1371/journal.pone.0189483] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Accepted: 11/27/2017] [Indexed: 12/20/2022] Open
Abstract
Carbohydrates from plant cell walls are often found as heteropolysaccharides intertwined with each other. For competitive advantage against other microorganisms, and ability to fully exploit available carbon and energy sources, Bacillus subtilis possesses a high number of proteins dedicated to the uptake of mono- and oligosaccharides. Here, we characterize transporter complexes, belonging to the ATP-binding cassette (ABC) superfamily, involved in the uptake of oligosaccharides commonly found in pectin. The uptake of these carbohydrates is shown to be MsmX-dependent, assigning a key role in pectin mobilization for MsmX, a multipurpose ATPase serving several distinct ABC-type I sugar importers. Mutagenesis analysis of the transmembrane domains of the AraNPQ MsmX-dependent importer revealed putative residues for MsmX interaction. Interestingly however, although MsmX is shown to be essential for energizing various ABC transporters we found that a second B. subtilis ATPase, YurJ, is able to complement its function when placed in trans at a different locus of the chromosome.
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Affiliation(s)
- Mário J. Ferreira
- UCIBIO, REQUIMTE, Departamento de Ciências da Vida, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, Caparica, Portugal
| | - Aristides L. Mendes
- UCIBIO, REQUIMTE, Departamento de Ciências da Vida, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, Caparica, Portugal
| | - Isabel de Sá-Nogueira
- UCIBIO, REQUIMTE, Departamento de Ciências da Vida, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, Caparica, Portugal
- * E-mail:
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A Novel Manno-Oligosaccharide Binding Protein Identified in Alkaliphilic Bacillus sp. N16-5 Is Involved in Mannan Utilization. PLoS One 2016; 11:e0150059. [PMID: 26978267 PMCID: PMC4792470 DOI: 10.1371/journal.pone.0150059] [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: 10/14/2015] [Accepted: 02/09/2016] [Indexed: 11/19/2022] Open
Abstract
ManH, a novel substrate-binding protein of an ABC transporter, was identified from the mannan utilization gene cluster of Bacillus sp. N16-5. We cloned, overexpressed, and purified ManH and measured its binding affinity to different substrates by isothermal titration calorimetry. ManH binds to mannotriose, mannotetraose, mannopentose, and galactosyl-mannotriose with dissociation constants in the micromolar range. Deletion of manH led to decreased growth ability of the strain when cultivated in medium with manno-oligosaccharides or mannan as the carbon source. ManH belongs to a manno-oligosaccharide transporter and plays an important role in mannan utilization by Bacillus sp. N16-5.
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Efficient fermentative production of polymer-grade D-lactate by an engineered alkaliphilic Bacillus sp. strain under non-sterile conditions. Microb Cell Fact 2016; 15:3. [PMID: 26754255 PMCID: PMC4709905 DOI: 10.1186/s12934-015-0408-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Accepted: 12/30/2015] [Indexed: 11/17/2022] Open
Abstract
Background Polylactic acid (PLA) is one important chemical building block that is well known as a biodegradable and a biocompatible plastic. The traditional lactate fermentation processes need CaCO3 as neutralizer to maintain the desired pH, which results in an amount of insoluble CaSO4 waste during the purification process. To overcome such environmental issue, alkaliphilic organisms have the great potential to be used as an organic acid producer under NaOH-neutralizing agent based fermentation. Additionally, high optical purity property in d-lactic acid is now attracting more attention from both scientific and industrial communities because it can improve mechanical properties of PLA by blending l- or d-polymer together. However, the use of low-price nitrogen source for d-lactate fermentation by alkaliphilic organisms combined with NaOH-neutralizing agent based process has not been studied. Therefore, our goal was the demonstrations of newly simplify high-optical-purity d-lactate production by using low-priced peanut meal combined with non-sterile NaOH-neutralizing agent based fermentation. Results In this study, we developed a process for high-optical-purity d-lactate production using an engineered alkaliphilic Bacillus strain. First, the native l-lactate dehydrogenase gene (ldh) was knocked out, and the d-lactate dehydrogenase gene from Lactobacillus delbrueckii was introduced to construct a d-lactate producer. The key gene responsible for exopolysaccharide biosynthesis (epsD) was subsequently disrupted to increase the yield and simplify the downstream process. Finally, a fed-batch fermentation under non-sterile conditions was conducted using low-priced peanut meal as a nitrogen source and NaOH as a green neutralizer. The d-lactate titer reached 143.99 g/l, with a yield of 96.09 %, an overall productivity of 1.674 g/l/h including with the highest productivity at 16 h of 3.04 g/l/h, which was even higher than that of a sterile fermentation. Moreover, high optical purities (approximately 99.85 %) of d-lactate were obtained under both conditions. Conclusions Given the use of a cheap nitrogen source and a non-sterile green fermentation process, this study provides a more valuable and favorable fermentation process for future polymer-grade d-lactate production.
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Yin L, Xue Y, Ma Y. Global Microarray Analysis of Alkaliphilic Halotolerant Bacterium Bacillus sp. N16-5 Salt Stress Adaptation. PLoS One 2015; 10:e0128649. [PMID: 26030352 PMCID: PMC4452262 DOI: 10.1371/journal.pone.0128649] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Accepted: 04/29/2015] [Indexed: 11/29/2022] Open
Abstract
The alkaliphilic halotolerant bacterium Bacillus sp. N16-5 is often exposed to salt stress in its natural habitats. In this study, we used one-colour microarrays to investigate adaptive responses of Bacillus sp. N16-5 transcriptome to long-term growth at different salinity levels (0%, 2%, 8%, and 15% NaCl) and to a sudden salt increase from 0% to 8% NaCl. The common strategies used by bacteria to survive and grow at high salt conditions, such as K+ uptake, Na+ efflux, and the accumulation of organic compatible solutes (glycine betaine and ectoine), were observed in Bacillus sp. N16-5. The genes of SigB regulon involved in general stress responses and chaperone-encoding genes were also induced by high salt concentration. Moreover, the genes regulating swarming ability and the composition of the cytoplasmic membrane and cell wall were also differentially expressed. The genes involved in iron uptake were down-regulated, whereas the iron homeostasis regulator Fur was up-regulated, suggesting that Fur may play a role in the salt adaption of Bacillus sp. N16-5. In summary, we present a comprehensive gene expression profiling of alkaliphilic Bacillus sp. N16-5 cells exposed to high salt stress, which would help elucidate the mechanisms underlying alkaliphilic Bacillus spp. survival in and adaptation to salt stress.
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Affiliation(s)
- Liang Yin
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yanfen Xue
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Yanhe Ma
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
- * E-mail: (YM)
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Profile of secreted hydrolases, associated proteins, and SlpA in Thermoanaerobacterium saccharolyticum during the degradation of hemicellulose. Appl Environ Microbiol 2014; 80:5001-11. [PMID: 24907337 DOI: 10.1128/aem.00998-14] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Thermoanaerobacterium saccharolyticum, a Gram-positive thermophilic anaerobic bacterium, grows robustly on insoluble hemicellulose, which requires a specialized suite of secreted and transmembrane proteins. We report here the characterization of proteins secreted by this organism. Cultures were grown on hemicellulose, glucose, xylose, starch, and xylan in pH-controlled bioreactors, and samples were analyzed via spotted microarrays and liquid chromatography-mass spectrometry. Key hydrolases and transporters employed by T. saccharolyticum for growth on hemicellulose were, for the most part, hitherto uncharacterized and existed in two clusters (Tsac_1445 through Tsac_1464 for xylan/xylose and Tsac_1344 through Tsac_1349 for starch). A phosphotransferase system subunit, Tsac_0032, also appeared to be exclusive to growth on glucose. Previously identified hydrolases that showed strong conditional expression changes included XynA (Tsac_1459), XynC (Tsac_0897), and a pullulanase, Apu (Tsac_1342). An omnipresent transcript and protein making up a large percentage of the overall secretome, Tsac_0361, was tentatively identified as the primary S-layer component in T. saccharolyticum, and deletion of the Tsac_0361 gene resulted in gross morphological changes to the cells. The view of hemicellulose degradation revealed here will be enabling for metabolic engineering efforts in biofuel-producing organisms that degrade cellulose well but lack the ability to catabolize C5 sugars.
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