Rhodobacteraceaeare the key members of the microbial community of the initial biofilm formed in Eastern Mediterranean coastal seawater

Abstract

The formation of biofilms and biofouling is a common feature in aquatic environments. The aim of this study was to identify the primary colonizers of biofilm formed in Eastern Mediterranean Coastal water at different seasons and follow early dynamics of biofilm community development. Pre-treated coastal seawater and biofilm samples were collected from six different sampling events of 2 weeks' duration each during 1 year. The microbial community composition and specific abundance were estimated by 16S rRNA gene clone libraries and fluorescence in situ hybridization-confocal laser scanning microscopy (FISH-CLSM), respectively. The biofilm formed over the course of the year was fairly consistent in terms of community composition and overall abundance with the exception of spring season. Alphaproteobacteria (30-70% of total bacteria), in particular Rhodobacteraceae, were the dominant bacteria in the biofilm, regardless of season, followed by Bacteroidetes (5-35%) and Gammaproteobacteria (6-35%). There was a decrease in relative abundance of Alphaproteobacteria and an increase in the abundance of Bacteroidetes between the initial and 2-week-old biofilm. This observation may aid man-made facilities that have to deal with biofilm formation and help the development of appropriate strategies to control those biofilms.

White Syndrome-Affected Corals Have a Distinct Microbiome at Disease Lesion Fronts

“…The presence of this taxon in healthy tissues, albeit at significantly lower levels, and the lack of bacterial infiltration into apparently healthy tissues immediately adjacent to (i.e., less than 1 cm ahead of) WS lesions suggest that Rhodobacteraceae bacteria rapidly colonize compromised tissues rather than drive the observed tissue loss. Members of the Rhodobacteraceae family are known to readily form biofilms in marine environments, which also suggests a role as opportunists rather than primary pathogens (36,37). The hypothesis that overall disruptions to the "core coral microbiome" could drive elevated Rhodobacteraceae levels in diseased samples is further supported by the observation of reductions in specific bacterial taxa, most notably Actinobacteria, which are prominent antibiotic producers and proposed members of the "core" coral microbiome (38,39).…”

Microbial Surface Colonization and Biofilm Development in Marine Environments

“…MRC bacteria have been identified as the key pioneer colonizers on both abiotic and biotic surfaces in marine environments (8,13,20,136,173,272,450,574,603,604). Recently, the iron-oxidizing Zetaproteobacteria were identified as a group of pioneer colonizers contributing to early-stage carbon steel biocorrosion in marine environments (18, 81).…”

“…Alphaproteobacteria (especially MRC bacteria) have been demonstrated to be the key primary surface colonizers in marine environments (8,13,20,173,272,450,604). However, the T6SSs are found primarily in Gammaproteobacteria among the marine bacteria (732).…”

Biofouling on Coated Carbon Steel in Cooling Water Cycles Using Brackish Seawater

“…The dominant alphaproteobacterial family was Rhodobacteraceae, which has previously been linked especially to early development of biofilm in marine environments, but also detected from this same environment earlier [28][29][30][31]. Many bacteria belonging to Rhodobacteraceae are known to perform phototrophic iron oxidation [32].…”

“…In addition, it has been speculated that the members of Rhodobacteraceae form the initial biofilm since they are able to survive on nutrient poor conditions of early stages of biofilm formation. Moreover, these microorganisms are capable of forming biofilm on copper-based biocidal antifouling coating [30,33].…”