Ecological function and interaction of different bacterial groups during alginate processing in coastal seawater community

• Published in: Environment international Vol. 182; p. 108325
• Main Authors: Cha, Qian-Qian, Liu, Sha-Sha, Dang, Yan-Ru, Ren, Xue-Bing, Xu, Fei, Li, Ping-Yi, Chen, Xiu-Lan, Wang, Peng, Zhang, Xi-Ying, Zhang, Yu-Zhong, Qin, Qi-Long
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Ltd 01.12.2023; Elsevier
• Subjects: Alginates - metabolism; Bacteria - genetics; Microbiota; Seawater - microbiology
• ISSN: 0160-4120; 1873-6750
• DOI: 10.1016/j.envint.2023.108325

•Different microbes in coastal seawater had distinct ecological roles in alginate metabolism process.•The main active degraders were a few genera from Gammaproteobacteria.•The scavenging strains were mainly from family Rhodobacteraceae.•Interaction of degrader and scavenging strains had no significant effect on the alginate degradation rate. The degradation of high molecular weight organic matter (HMWOM) is a core process of oceanic carbon cycle, which is determined by the activity of microbial communities harboring hundreds of different species. Illustrating the active microbes and their interactions during HMWOM processing can provide key information for revealing the relationship between community composition and its ecological functions. In this study, the genomic and transcriptional responses of microbial communities to the availability of alginate, an abundant HMWOM in coastal ecosystem, were elucidated. The main degraders transcribing alginate lyase (Aly) genes came from genera Alteromonas, Psychrosphaera and Colwellia. Meanwhile, some strains, mainly from the Rhodobacteraceae family, did not transcribe Aly gene but could utilize monosaccharides to grow. The co-culture experiment showed that the activity of Aly-producing strain could promote the growth of Aly-non-producing strain when alginate was the sole carbon source. Interestingly, this interaction did not reduce the alginate degradation rate, possibly due to the easily degradable nature of alginate. This study can improve our understanding of the relationship between microbial community activity and alginate metabolism function as well as further manipulation of microbial community structure for alginate processing.