Open AccessResponse of bacterioplankton to a glucose gradient in the absence of lysis and grazing
Author(s) -
Zhang Rui,
Weinbauer Markus G.,
Tam Yin Ki,
Qian PeiYuan
Publication year - 2013
Publication title -
fems microbiology ecology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.377
H-Index - 155
eISSN - 1574-6941
pISSN - 0168-6496
DOI - 10.1111/1574-6941.12133
Subject(s) - bacterioplankton , biology , temperature gradient gel electrophoresis , mixotroph , dissolved organic carbon , microbial loop , microbial population biology , heterotroph , nutrient , bacteria , microbiology and biotechnology , food science , ecology , phytoplankton , genetics , 16s ribosomal rna
Bacterial utilization of dissolved organic matter plays an important role in marine carbon cycling. In this study, the response of bacterioplankton to a gradient of carbon (glucose) addition was investigated experimentally in a subtropical coastal environment in the absence of top‐down control by viruses and flagellates. Bacterial abundance and production were stimulated by glucose addition corresponding to a gradient of glucose. Differences in the extent of stimulation suggested different bacterial life strategies under different nutrient conditions. Bacterial community diversity as revealed by denaturing gradient gel electrophoresis ( DGGE ) showed a unimodal productivity–diversity (number of DGGE bands) relationship after 3‐day incubation. DNA fingerprinting profiling and cluster analysis showed clear and gradual changes in bacterial community structure along the gradient of glucose concentrations, reflecting the competition for carbon supply among bacterial groups. Sequencing analysis of the DGGE bands disclosed the relative abundance of seven bacterial genotypes in the A lteromonadaceae and R oseovarius that gradually decreased with the glucose enrichment while two V ibrio genotypes showed the reverse increasing trend. This suggested that V ibrio was a more successful opportunist at high carbon availability.