Open AccessDifferential Incorporation of Carbon Substrates among Microbial Populations Identified by Field-Based, DNA Stable-Isotope Probing in South China Sea
Author(s) -
Yao Zhang,
Wenchao Deng,
Xiabing Xie,
Nianzhi Jiao
Publication year - 2016
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0157178
Subject(s) - stable isotope probing , pyrosequencing , biology , terminal restriction fragment length polymorphism , dissolved organic carbon , roseobacter , microbial population biology , population , 16s ribosomal rna , environmental chemistry , microorganism , ecology , bacteria , clade , phylogenetics , restriction fragment length polymorphism , biochemistry , chemistry , genetics , polymerase chain reaction , gene , demography , sociology
To determine the adapted microbial populations to variant dissolved organic carbon (DOC) sources in the marine environment and improve the understanding of the interaction between microorganisms and marine DOC pool, field-based incubation experiments were carried out using supplemental 13 C-labeled typical substrates D -glucose and D -glucosamine ( D -Glc and D -GlcN, respectively), which are two important components in marine DOC pool in the South China Sea. 13 C- and 12 C-DNA were then fractionated by ultracentrifugation and the microbial community was analyzed by terminal-restriction fragment length polymorphism and 454 pyrosequencing of 16S rRNA gene. 12 C-DNA-based communities showed relatively high similarities with their corresponding in situ communities, and their bacterial diversities were generally higher than 13 C-DNA-based counterparts. Distinct differences in community composition were found between 13 C- and 12 C-DNA-based communities and between two substrate-supplemented 13 C-DNA-based communities; these differences distinctly varied with depth and site. In most cases, there were more genera with relative abundances of >0.1% in D -Glc-incorporating communities than in D -GlcN-incorporating communities. The Roseobacter clade was one of the prominent actively substrate-incorporating bacterial populations in all 13 C-DNA-based communities. Vibrio was another prominent actively D -GlcN-incorporating bacterial population in most incubations. However notably, different OTUs dominated this clade or genus in different treatments at different depths. Altogether, these results suggested that there were taxa-specific differences in DOC assimilations and, moreover, their differences varied among the typical water masses, which could have been caused by the variant compositions of original bacterial communities from different hydrological environments. This implies that ecologically, the levels of labile or recalcitrance of DOC can be maintained only in a specific environmental context with specific bacterial community composition.