Structural and functional patterns of active bacterial communities during aging of harpacticoid copepod fecal pellets

Aquatic Microbial Ecology

Tom Moens¹  Clio Cnudde¹  Marleen De Troch¹  Chelmarie Joy Sanchez Clavano¹  Anne Willems¹ 

关键词: Copepod fecal pellet;    Fecal pellet degradation;    Active bacterial communities;    Harpacticoid copepods;    16S rRNA;    DGGE;    Biolog EcoPlate™;   

DOI  :  10.3354/ame01663

学科分类：生物科学（综合）

来源: Inter-Research

【 摘 要 】

ABSTRACT: Copepod fecal pellet (fp) dissolved organic matter is consumed by free-living bacteria, while particulate matter is degraded by bacteria packed inside the fp (‘internal�?) or attached to the fp surface after colonization from the environment (external). This study analyzed the contribution of ‘internal�? and external fp bacteria to the active bacterial community associated with the fp from 2 copepod species, Paramphiascella fulvofasciata and Platychelipus littoralis, during 60 h of fp aging in seawater. Despite early colonization (within 20 to 40 h), fp enrichment by seawater bacteria, as deduced from RNA-based DGGE after 60 h, was limited. In contrast, ‘internal�? bacteria showed high phylotype richness. The majority of ‘internal�? bacterial phylotypes persisted on aged fp and together represented half of the active bacterial community. Food source strongly impacted ‘internal�? bacterial diversity, though the exact origin of fp ‘internal�? bacteria, as either undigested food-associated bacteria or as copepod gut bacteria, could not be unambiguously determined. ‘Internal�? bacteria of fresh fp showed a high functional diversity (based on Biolog assays) to which Vibrio sp. contributed significantly. In terms of bacterial diversity and functional potential, degradation of copepod fp by ‘internal�? bacteria is equally as important as degradation by bacteria which colonize fp from the outside.

【 授权许可】

Unknown