Hidden interactions in the intertidal rocky shore: variation in pedal mucus microbiota among marine grazers that feed on epilithic biofilm communities

PeerJ

article

Clara Arboleda-Baena¹  Claudia Belén Pareja²  Isadora Pla²  Ramiro Logares³  Rodrigo De la Iglesia²  Sergio Andrés Navarrete¹ 

[1] Estación Costera de Investigaciones Marinas and Center for Applied Ecology and Sustainability ,(CAPES), Pontificia Universidad Católica de Chile;Departamento de Genética Molecular y Microbiología, Pontificia Universidad Católica de Chile;Institut de Ciències del Mar;Marine Energy Research & Innovation Center;Centro Basal COPAS-COASTAL, Universidad de Concepción

关键词: Mollusk;    Grazers;    Epilithic biofilm;    Intertidal;    Pedal mucus microbiota;   

DOI  :  10.7717/peerj.13642

学科分类：社会科学、人文和艺术（综合）

来源: Inra

【 摘 要 】

In marine ecosystems, most invertebrates possess diverse microbiomes on their external surfaces, such as those found in the pedal mucus of grazing gastropods and chitons that aids displacement on different surfaces. The microbes are then transported around and placed in contact with free-living microbial communities of micro and other macro-organisms, potentially exchanging species and homogenizing microbial composition and structure among grazer hosts. Here, we characterize the microbiota of the pedal mucus of five distantly related mollusk grazers, quantify differences in microbial community structure, mucus protein and carbohydrate content, and, through a simple laboratory experiment, assess their effects on integrated measures of biofilm abundance. Over 665 Amplicon Sequence Variants (ASVs) were found across grazers, with significant differences in abundance and composition among grazer species and epilithic biofilms. The pulmonate limpet Siphonaria lessonii and the periwinkle Echinolittorina peruviana shared similar microbiota. The microbiota of the chiton Chiton granosus, keyhole limpet Fissurella crassa, and scurrinid limpet Scurria araucana differed markedly from one another, and form those of the pulmonate limpet and periwinkle. Flavobacteriaceae (Bacteroidia) and Colwelliaceae (Gammaproteobacteria) were the most common among microbial taxa. Microbial strict specialists were found in only one grazer species. The pedal mucus pH was similar among grazers, but carbohydrate and protein concentrations differed significantly. Yet, differences in mucus composition were not reflected in microbial community structure. Only the pedal mucus of F. crassa and S. lessonii negatively affected the abundance of photosynthetic microorganisms in the biofilm, demonstrating the specificity of the pedal mucus effects on biofilm communities. Thus, the pedal mucus microbiota are distinct among grazer hosts and can affect and interact non-trophically with the epilithic biofilms on which grazers feed, potentially leading to microbial community coalescence mediated by grazer movement. Further studies are needed to unravel the myriad of non-trophic interactions and their reciprocal impacts between macro- and microbial communities.

【 授权许可】

CC BY