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Rønne ME, Tandrup T, Madsen M, Hunt CJ, Myers PN, Moll JM, Holck J, Brix S, Strube ML, Aachmann FL, Wilkens C, Svensson B. Three alginate lyases provide a new gut Bacteroides ovatus isolate with the ability to grow on alginate. Appl Environ Microbiol 2023; 89:e0118523. [PMID: 37791757 PMCID: PMC10617595 DOI: 10.1128/aem.01185-23] [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: 07/20/2023] [Accepted: 08/03/2023] [Indexed: 10/05/2023] Open
Abstract
Humans consume alginate in the form of seaweed, food hydrocolloids, and encapsulations, making the digestion of this mannuronic acid (M) and guluronic acid (G) polymer of key interest for human health. To increase knowledge on alginate degradation in the gut, a gene catalog from human feces was mined for potential alginate lyases (ALs). The predicted ALs were present in nine species of the Bacteroidetes phylum, of which two required supplementation of an endo-acting AL, expected to mimic cross-feeding in the gut. However, only a new isolate grew on alginate. Whole-genome sequencing of this alginate-utilizing isolate suggested that it is a new Bacteroides ovatus strain harboring a polysaccharide utilization locus (PUL) containing three ALs of families: PL6, PL17, and PL38. The BoPL6 degraded polyG to oligosaccharides of DP 1-3, and BoPL17 released 4,5-unsaturated monouronate from polyM. BoPL38 degraded both alginates, polyM, polyG, and polyMG, in endo-mode; hence, it was assumed to deliver oligosaccharide substrates for BoPL6 and BoPL17, corresponding well with synergistic action on alginate. BoPL17 and BoPL38 crystal structures, determined at 1.61 and 2.11 Å, respectively, showed (α/α)6-barrel + anti-parallel β-sheet and (α/α)7-barrel folds, distinctive for these PL families. BoPL17 had a more open active site than the two homologous structures. BoPL38 was very similar to the structure of an uncharacterized PL38, albeit with a different triad of residues possibly interacting with substrate in the presumed active site tunnel. Altogether, the study provides unique functional and structural insights into alginate-degrading lyases of a PUL in a human gut bacterium.IMPORTANCEHuman ingestion of sustainable biopolymers calls for insight into their utilization in our gut. Seaweed is one such resource with alginate, a major cell wall component, used as a food hydrocolloid and for encapsulation of pharmaceuticals and probiotics. Knowledge is sparse on the molecular basis for alginate utilization in the gut. We identified a new Bacteroides ovatus strain from human feces that grew on alginate and encoded three alginate lyases in a gene cluster. BoPL6 and BoPL17 show complementary specificity toward guluronate (G) and mannuronate (M) residues, releasing unsaturated oligosaccharides and monouronic acids. BoPL38 produces oligosaccharides degraded by BoPL6 and BoPL17 from both alginates, G-, M-, and MG-substrates. Enzymatic and structural characterization discloses the mode of action and synergistic degradation of alginate by these alginate lyases. Other bacteria were cross-feeding on alginate oligosaccharides produced by an endo-acting alginate lyase. Hence, there is an interdependent community in our guts that can utilize alginate.
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Affiliation(s)
- Mette E. Rønne
- Department of Biotechnology and Biomedicine, Enzyme and Protein Chemistry, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Tobias Tandrup
- Department of Biotechnology and Biomedicine, Enzyme and Protein Chemistry, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Mikkel Madsen
- Department of Biotechnology and Biomedicine, Enzyme and Protein Chemistry, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Cameron J. Hunt
- Department of Biotechnology and Biomedicine, Enzyme Technology, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Pernille N. Myers
- Department of Biotechnology and Biomedicine, Disease Systems Immunology, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Janne M. Moll
- Department of Biotechnology and Biomedicine, Disease Systems Immunology, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Jesper Holck
- Department of Biotechnology and Biomedicine, Enzyme Technology, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Susanne Brix
- Department of Biotechnology and Biomedicine, Disease Systems Immunology, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Mikael L. Strube
- Department of Biotechnology and Biomedicine, Bacterial Ecophysiology and Biotechnology, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Finn L. Aachmann
- Department of Biotechnology and Food Science, Norwegian Biopolymer Laboratory (NOBIPOL), NTNU Norwegian University of Science and Technology, Trondheim, Norway
| | - Casper Wilkens
- Department of Biotechnology and Biomedicine, Enzyme Technology, Technical University of Denmark, Kgs. Lyngby, Denmark
- Department of Biotechnology and Biomedicine, Structural Enzymology, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Birte Svensson
- Department of Biotechnology and Biomedicine, Enzyme and Protein Chemistry, Technical University of Denmark, Kgs. Lyngby, Denmark
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Dar MA, Dhole NP, Xie R, Pawar KD, Ullah K, Rahi P, Pandit RS, Sun J. Valorization Potential of a Novel Bacterial Strain, Bacillus altitudinis RSP75, towards Lignocellulose Bioconversion: An Assessment of Symbiotic Bacteria from the Stored Grain Pest, Tribolium castaneum. Microorganisms 2021; 9:microorganisms9091952. [PMID: 34576846 PMCID: PMC8468446 DOI: 10.3390/microorganisms9091952] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 09/09/2021] [Accepted: 09/09/2021] [Indexed: 12/26/2022] Open
Abstract
Bioconversion of lignocellulose into renewable energy and commodity products faces a major obstacle of inefficient saccharification due to its recalcitrant structure. In nature, lignocellulose is efficiently degraded by some insects, including termites and beetles, potentially due to the contribution from symbiotic gut bacteria. To this end, the presented investigation reports the isolation and characterization of cellulolytic bacteria from the gut system of red flour beetle, Tribolium castaneum. Out of the 15 isolated bacteria, strain RSP75 showed the highest cellulolytic activities by forming a clearance zone of 28 mm in diameter with a hydrolytic capacity of ~4.7. The MALDI-TOF biotyping and 16S rRNA gene sequencing revealed that the strain RSP75 belongs to Bacillus altitudinis. Among the tested enzymes, B. altitudinis RSP75 showed maximum activity of 63.2 IU/mL extract for xylanase followed by β-glucosidase (47.1 ± 3 IU/mL extract) which were manifold higher than previously reported activities. The highest substrate degradation was achieved with wheat husk and corn cob powder which accounted for 69.2% and 54.5%, respectively. The scanning electron microscopy showed adhesion of the bacterial cells with the substrate which was further substantiated by FTIR analysis that depicted the absence of the characteristic cellulose bands at wave numbers 1247, 1375, and 1735 cm-1 due to hydrolysis by the bacterium. Furthermore, B. altitudinis RSP75 showed co-culturing competence with Saccharomyces cerevisiae for bioethanol production from lignocellulose as revealed by GC-MS analysis. The overall observations signify the gut of T. castaneum as a unique and impressive reservoir to prospect for lignocellulose-degrading bacteria that can have many biotechnological applications, including biofuels and biorefinery.
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Affiliation(s)
- Mudasir A. Dar
- Biofuels Institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang 212013, China or (M.A.D.); (R.X.)
- Department of Zoology, Savitribai Phule Pune University, Ganeshkhind, Pune 411007, India;
| | - Neeraja P. Dhole
- Department of Zoology, Savitribai Phule Pune University, Ganeshkhind, Pune 411007, India;
| | - Rongrong Xie
- Biofuels Institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang 212013, China or (M.A.D.); (R.X.)
| | - Kiran D. Pawar
- School of Nanoscience and Biotechnology, Shivaji University, Vidyanagar, Kolhapur 416004, India;
| | - Kalim Ullah
- School of Medicine, Jiangsu University, Zhenjiang 212013, China;
| | - Praveen Rahi
- National Centre for Microbial Research, Trinity Complex, Pashan, Pune 411021, India;
| | - Radhakrishna S. Pandit
- Department of Zoology, Savitribai Phule Pune University, Ganeshkhind, Pune 411007, India;
- Correspondence: (R.S.P.); (J.S.)
| | - Jianzhong Sun
- Biofuels Institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang 212013, China or (M.A.D.); (R.X.)
- Correspondence: (R.S.P.); (J.S.)
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A Novel Auxiliary Agarolytic Pathway Expands Metabolic Versatility in the Agar-Degrading Marine Bacterium Colwellia echini A3 T. Appl Environ Microbiol 2021; 87:e0023021. [PMID: 33811026 DOI: 10.1128/aem.00230-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Marine microorganisms encode a complex repertoire of carbohydrate-active enzymes (CAZymes) for the catabolism of algal cell wall polysaccharides. While the core enzyme cascade for degrading agar is conserved across agarolytic marine bacteria, gain of novel metabolic functions can lead to the evolutionary expansion of the gene repertoire. Here, we describe how two less-abundant GH96 α-agarases harbored in the agar-specific polysaccharide utilization locus (PUL) of Colwellia echini strain A3T facilitate the versatility of the agarolytic pathway. The cellular and molecular functions of the α-agarases examined by genomic, transcriptomic, and biochemical analyses revealed that α-agarases of C. echini A3T create a novel auxiliary pathway. α-Agarases convert even-numbered neoagarooligosaccharides to odd-numbered agaro- and neoagarooligosaccharides, providing an alternative route for the depolymerization process in the agarolytic pathway. Comparative genomic analysis of agarolytic bacteria implied that the agarolytic gene repertoire in marine bacteria has been diversified during evolution, while the essential core agarolytic gene set has been conserved. The expansion of the agarolytic gene repertoire and novel hydrolytic functions, including the elucidated molecular functionality of α-agarase, promote metabolic versatility by channeling agar metabolism through different routes. IMPORTANCE Colwellia echini A3T is an example of how the gain of gene(s) can lead to the evolutionary expansion of agar-specific polysaccharide utilization loci (PUL). C. echini A3T encodes two α-agarases in addition to the core β-agarolytic enzymes in its agarolytic PUL. Among the agar-degrading CAZymes identified so far, only a few α-agarases have been biochemically characterized. The molecular and biological functions of two α-agarases revealed that their unique hydrolytic pattern leads to the emergence of auxiliary agarolytic pathways. Through the combination of transcriptomic, genomic, and biochemical evidence, we elucidate the complete α-agarolytic pathway in C. echini A3T. The addition of α-agarases to the agarolytic enzyme repertoire might allow marine agarolytic bacteria to increase competitive abilities through metabolic versatility.
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Dharani SR, Srinivasan R, Sarath R, Ramya M. Recent progress on engineering microbial alginate lyases towards their versatile role in biotechnological applications. Folia Microbiol (Praha) 2020; 65:937-954. [DOI: 10.1007/s12223-020-00802-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Accepted: 05/16/2020] [Indexed: 11/30/2022]
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A Multifunctional Polysaccharide Utilization Gene Cluster in Colwellia echini Encodes Enzymes for the Complete Degradation of κ-Carrageenan, ι-Carrageenan, and Hybrid β/κ-Carrageenan. mSphere 2020; 5:5/1/e00792-19. [PMID: 31915221 PMCID: PMC6952198 DOI: 10.1128/msphere.00792-19] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Here, we report that a recently described bacterium, Colwellia echini, harbors a large number of enzymes enabling the bacterium to grow on κ-carrageenan and agar. The genes are organized in two clusters that encode enzymes for the total degradation of κ-carrageenan and agar, respectively. As the first, we report on the structure/function relationship of a new class of enzymes that hydrolyze furcellaran, a partially sulfated β/κ-carrageenan. Using an in silico model, we hypothesize a molecular structure of furcellaranases and compare structural features and active site architectures of furcellaranases with those of other GH16 polysaccharide hydrolases, such as κ-carrageenases, β-agarases, and β-porphyranases. Furthermore, we describe a new class of enzymes distantly related to GH42 and GH160 β-galactosidases and show that this new class of enzymes is active only on hybrid β/κ-carrageenan oligosaccharides. Finally, we propose a new model for how the carrageenolytic enzyme repertoire enables C. echini to metabolize β/κ-, κ-, and ι-carrageenan. Algal cell wall polysaccharides constitute a large fraction in the biomass of marine primary producers and are thus important in nutrient transfer between trophic levels in the marine ecosystem. In order for this transfer to take place, polysaccharides must be degraded into smaller mono- and disaccharide units, which are subsequently metabolized, and key components in this degradation are bacterial enzymes. The marine bacterium Colwellia echini A3T is a potent enzyme producer since it completely hydrolyzes agar and κ-carrageenan. Here, we report that the genome of C. echini A3T harbors two large gene clusters for the degradation of carrageenan and agar, respectively. Phylogenetical and functional studies combined with transcriptomics and in silico structural modeling revealed that the carrageenolytic cluster encodes furcellaranases, a new class of glycoside hydrolase family 16 (GH16) enzymes that are key enzymes for hydrolysis of furcellaran, a hybrid carrageenan containing both β- and κ-carrageenan motifs. We show that furcellaranases degrade furcellaran into neocarratetraose-43-O-monosulfate [DA-(α1,3)-G4S-(β1,4)-DA-(α1,3)-G], and we propose a molecular model of furcellaranases and compare the active site architectures of furcellaranases, κ-carrageenases, β-agarases, and β-porphyranases. Furthermore, C. echini A3T was shown to encode κ-carrageenases, ι-carrageenases, and members of a new class of enzymes, active only on hybrid β/κ-carrageenan tetrasaccharides. On the basis of our genomic, transcriptomic, and functional analyses of the carrageenolytic enzyme repertoire, we propose a new model for how C. echini A3T degrades complex sulfated marine polysaccharides such as furcellaran, κ-carrageenan, and ι-carrageenan. IMPORTANCE Here, we report that a recently described bacterium, Colwellia echini, harbors a large number of enzymes enabling the bacterium to grow on κ-carrageenan and agar. The genes are organized in two clusters that encode enzymes for the total degradation of κ-carrageenan and agar, respectively. As the first, we report on the structure/function relationship of a new class of enzymes that hydrolyze furcellaran, a partially sulfated β/κ-carrageenan. Using an in silico model, we hypothesize a molecular structure of furcellaranases and compare structural features and active site architectures of furcellaranases with those of other GH16 polysaccharide hydrolases, such as κ-carrageenases, β-agarases, and β-porphyranases. Furthermore, we describe a new class of enzymes distantly related to GH42 and GH160 β-galactosidases and show that this new class of enzymes is active only on hybrid β/κ-carrageenan oligosaccharides. Finally, we propose a new model for how the carrageenolytic enzyme repertoire enables C. echini to metabolize β/κ-, κ-, and ι-carrageenan.
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Ito M, Watanabe K, Maruyama T, Mori T, Niwa K, Chow S, Takeyama H. Enrichment of bacteria and alginate lyase genes potentially involved in brown alga degradation in the gut of marine gastropods. Sci Rep 2019; 9:2129. [PMID: 30765748 PMCID: PMC6375959 DOI: 10.1038/s41598-018-38356-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Accepted: 12/17/2018] [Indexed: 02/02/2023] Open
Abstract
Gut bacteria of phytophagous and omnivorous marine invertebrates often possess alginate lyases (ALGs), which are key enzymes for utilizing macroalgae as carbon neutral biomass. We hypothesized that the exclusive feeding of a target alga to marine invertebrates would shift the gut bacterial diversity suitable for degrading the algal components. To test this hypothesis, we reared sea hare (Dolabella auricularia) and sea snail (Batillus cornutus) for two to four weeks with exclusive feeding of a brown alga (Ecklonia cava). Pyrosequencing analysis of the gut bacterial 16S rRNA genes revealed shifts in the gut microbiota after rearing, mainly due to a decrease in the variety of bacterial members. Significant increases in six and four 16S rRNA gene phylotypes were observed in the reared sea hares and sea snails, respectively, and some of them were phylogenetically close to known alginate-degrading bacteria. Clone library analysis of PL7 family ALG genes using newly designed degenerate primer sets detected a total of 50 ALG gene phylotypes based on 90% amino acid identity. The number of ALG gene phylotypes increased in the reared sea hare but decreased in reared sea snail samples, and no phylotype was shared between them. Out of the 50 phylotypes, 15 were detected only after the feeding procedure. Thus, controlled feeding strategy may be valid and useful for the efficient screening of genes suitable for target alga fermentation.
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Affiliation(s)
- Michihiro Ito
- Research Organization for Nano & Life Innovation, Waseda University, 513 Wasedatsurumaki-cho, Shinjuku, Tokyo, 162-0041, Japan
- Tropical Biosphere Research Center, University of the Ryukyus, 1 Senbaru, Nishihara, Okinawa, 903-0213, Japan
| | - Kotaro Watanabe
- Department of Life Science and Medical Bioscience, Waseda University, 2-2 Wakamatsu-cho, Shinjuku, Tokyo, 162-8480, Japan
| | - Toru Maruyama
- Department of Life Science and Medical Bioscience, Waseda University, 2-2 Wakamatsu-cho, Shinjuku, Tokyo, 162-8480, Japan
| | - Tetsushi Mori
- International Center for Science and Engineering Programs, Waseda University, 3-4-1 Okubo, Shinjuku-ku, Tokyo, 169-8555, Japan
- Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Koganei, Tokyo, 184-8588, Japan
| | - Kentaro Niwa
- National Research Institute of Fisheries Science, 2-12-4 Fukuura, Kanazawa, Yokohama, Kanagawa, 236-8648, Japan
| | - Seinen Chow
- National Research Institute of Fisheries Science, 2-12-4 Fukuura, Kanazawa, Yokohama, Kanagawa, 236-8648, Japan
| | - Haruko Takeyama
- Research Organization for Nano & Life Innovation, Waseda University, 513 Wasedatsurumaki-cho, Shinjuku, Tokyo, 162-0041, Japan.
- Department of Life Science and Medical Bioscience, Waseda University, 2-2 Wakamatsu-cho, Shinjuku, Tokyo, 162-8480, Japan.
- Institute for Advanced Research of Biosystem Dynamics, Waseda University, 2-2 Wakamatsu-cho, Shinjuku, Tokyo, 162-8480, Japan.
- Computational Bio Big-Data Open Innovation Laboratory, AIST-Waseda University, 3-4-1 Okubo, Shinjuku, Tokyo, 169-0072, Japan.
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Exploring the gut of Helicoverpa armigera for cellulose degrading bacteria and evaluation of a potential strain for lignocellulosic biomass deconstruction. Process Biochem 2018. [DOI: 10.1016/j.procbio.2018.08.001] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Dudek M, Adams J, Swain M, Hegarty M, Huws S, Gallagher J. Metaphylogenomic and potential functionality of the limpet Patella pellucida's gastrointestinal tract microbiome. Int J Mol Sci 2014; 15:18819-39. [PMID: 25334059 PMCID: PMC4227249 DOI: 10.3390/ijms151018819] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Revised: 09/30/2014] [Accepted: 10/11/2014] [Indexed: 11/16/2022] Open
Abstract
This study investigated the microbial diversity associated with the digestive tract of the seaweed grazing marine limpet Patella pellucida. Using a modified indirect DNA extraction protocol and performing metagenomic profiling based on specific prokaryotic marker genes, the abundance of bacterial groups was identified from the analyzed metagenome. The members of three significantly abundant phyla of Proteobacteria, Firmicutes and Bacteroidetes were characterized through the literature and their predicted functions towards the host, as well as potential applications in the industrial environment assessed.
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Affiliation(s)
- Magda Dudek
- Institute of Biological, Environmental & Rural Sciences (IBERS), Aberystwyth University, Gogerddan, Aberystwyth, Ceredigion, Wales SY23 3EE, UK.
| | - Jessica Adams
- Institute of Biological, Environmental & Rural Sciences (IBERS), Aberystwyth University, Gogerddan, Aberystwyth, Ceredigion, Wales SY23 3EE, UK.
| | - Martin Swain
- Institute of Biological, Environmental & Rural Sciences (IBERS), Aberystwyth University, Gogerddan, Aberystwyth, Ceredigion, Wales SY23 3EE, UK.
| | - Matthew Hegarty
- Institute of Biological, Environmental & Rural Sciences (IBERS), Aberystwyth University, Gogerddan, Aberystwyth, Ceredigion, Wales SY23 3EE, UK.
| | - Sharon Huws
- Institute of Biological, Environmental & Rural Sciences (IBERS), Aberystwyth University, Gogerddan, Aberystwyth, Ceredigion, Wales SY23 3EE, UK.
| | - Joe Gallagher
- Institute of Biological, Environmental & Rural Sciences (IBERS), Aberystwyth University, Gogerddan, Aberystwyth, Ceredigion, Wales SY23 3EE, UK.
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Kim EJ, Fathoni A, Jeong GT, Jeong HD, Nam TJ, Kong IS, Kim JK. Microbacterium oxydans, a novel alginate- and laminarin-degrading bacterium for the reutilization of brown-seaweed waste. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2013; 130:153-159. [PMID: 24076515 DOI: 10.1016/j.jenvman.2013.08.064] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2013] [Revised: 08/25/2013] [Accepted: 08/31/2013] [Indexed: 06/02/2023]
Abstract
There is a growing demand for the efficient treatment of seaweed waste. We identified six bacterial strains from the marine environment for the reutilization of brown-seaweed waste, and the most potentially useful strain, Microbacterium oxydans, was chosen and further investigated. Plate assays indicated that this bacterial isolate possessed both alginate lyase and laminarinase activities. The optimal inoculum size, pH, temperature and substrate concentration for the degradation of brown-seaweed polysaccharides by the isolate were as follows: 20% (v v(-1)), pH 6.0, 37 °C, and 5 g L(-1) for alginate and 20% (v v(-1)), pH 6.0, 30 °C, and 10 g L(-1) for laminarin, respectively. During 6 d in culture under the optimal conditions, the isolate produced 0.17 g L(-1) of reducing sugars from alginate with 11.0 U mL(-1) of maximal alginate lyase activity, and 5.11 and 2.88 g L(-1) of reducing sugars and glucose from laminarin, respectively. In particular, a fair amount of laminarin was degraded to glucose (28.8%) due to the isolate's exolytic laminarinase activity. As a result, the reutilization of brown-seaweed waste by this isolate appears to be possible for the production of reducing sugars as a valuable resource. This is the first study to directly demonstrate the ability of M. oxydans to degrade both alginate and laminarin.
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Affiliation(s)
- Eun Jung Kim
- Department of Biotechnology, Pukyong National University, Busan 608-737, Republic of Korea
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