Metagenomic analysis of a keratin-degrading bacterial consortium provides insight into the keratinolytic mechanisms.

Keratinases; Metabolic cooperation; Metabolic pathways; Metagenome-assembled genomes; Microbial community; Keratins; Bacteria/genetics; Biodegradation, Environmental; Metagenomics; Metagenome; Amino acid metabolism; Bacterial consortium; Disulfide reduction; Keratinolytic activity; Metagenomic analysis; Natural environments; Synergistic interaction; Value added products; Bacteria; Environmental Engineering; Environmental Chemistry; Waste Management and Disposal; Pollution

Abstract :

[en] Keratin is an insoluble fibrous protein from natural environments, which can be recycled to value-added products by keratinolytic microorganisms. A microbial consortium with efficient keratinolytic activity was previously enriched from soil, but the genetic basis behind its remarkable degradation properties was not investigated yet. To identify the metabolic pathways involved in keratinolysis and clarify the observed synergy among community members, shotgun metagenomic sequencing was performed to reconstruct metagenome-assembled genomes. More than 90% genera of the enriched bacterial consortium were affiliated to Chryseobacterium, Stenotrophomonas, and Pseudomonas. Metabolic potential and putative keratinases were predicted from the metagenomic annotation, providing the genetic basis of keratin degradation. Furthermore, metabolic pathways associated with keratinolytic processes such as amino acid metabolism, disulfide reduction and urea cycle were investigated from seven high-quality metagenome-assembled genomes, revealing the potential metabolic cooperation related to keratin degradation. This knowledge deepens the understanding of microbial keratinolytic mechanisms at play in a complex community, pinpointing the significance of synergistic interactions, which could be further used to optimize industrial keratin degradation processes.

Disciplines :

Microbiology

Author, co-author :

Kang, Dingrong ; Université de Liège - ULiège > Département GxABT > Microbial technologies

Huang, Yuhong; Department of Biotechnology and Biomedicine, Technical University of Denmark, Building 224, Søltofts Plads, 2800 Kongens Lyngby, Denmark, Beijing Key Laboratory of Ionic Liquids Clean Process, Key Laboratory of Green Process and Engineering, State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, PR China

Nesme, Joseph; Section of Microbiology, Department of Biology, University of Copenhagen, Copenhagen, Denmark

Herschend, Jakob; Section of Microbiology, Department of Biology, University of Copenhagen, Copenhagen, Denmark

Jacquiod, Samuel; Section of Microbiology, Department of Biology, University of Copenhagen, Copenhagen, Denmark, Agroécologie, AgroSup Dijon, INRA, Univ. Bourgogne Franche-Comté, France

Kot, Witold; Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg, Denmark

Hansen, Lars Hestbjerg; Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg, Denmark

Lange, Lene; Department of Biotechnology and Biomedicine, Technical University of Denmark, Building 224, Søltofts Plads, 2800 Kongens Lyngby, Denmark, Bioeconomy, Research & Advisory, Karensgade 5, DK-2500 Valby, Denmark

Sørensen, Søren J; Section of Microbiology, Department of Biology, University of Copenhagen, Copenhagen, Denmark. Electronic address: sjs@bio.ku.dk

Language :

English

Title :

Metagenomic analysis of a keratin-degrading bacterial consortium provides insight into the keratinolytic mechanisms.

Publication date :

20 March 2021

Journal title :

Science of the Total Environment

ISSN :

0048-9697

eISSN :

1879-1026

Publisher :

Elsevier B.V., Netherlands

Volume :

761

Pages :

143281

Peer reviewed :

Peer Reviewed verified by ORBi

Additional URL :

https://api.elsevier.com/content/article/PII:S0048969720368121?httpAccept=text/xml

Funders :

Chinese Government Scholarship
Innovationsfonden

Funding text :

This research was funded by the Danish Innovation Fund (grant number 1308-00015B , Keratin2Protein) and also under the support of the Chinese Scholarship Council (CSC) Scholarship Program.

Available on ORBi :

since 25 August 2022

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