Prokaryotic diversity revealed by Denaturing Gradient Gel Electrophoresis (DGGE) in the East Sea during 2007-2009

Abstract

To understand temporal and spatial changes of the prokaryotic (archaea and bacteria) diversity in the East Sea, the prokaryotic community composition was determined by denaturing gradient gel electrophoresis (DGGE) technique. The investigations were conducted four times between 2007 and 2009 and water samples were obtained from 0 m, 50 m, 200 m and 700-800 m depths in coastal and offshore stations. The prokaryotic abundance, leucine incorporation rate and other environmental parameters were also measured. By PCR-DGGE-sequencing approach, we obtained 284 bacterial sequences and 166 archaeal sequences, respectively.The most frequently detected phylotypes were Alpha-proteobacteria, Gamma-proteobacteria, Bacteroidetes, Cyanobacteria, and Euryarchaeota. Actinobacteria, and Thaumarchaeota were occasionally detected. Most of the phylotypes were more closely related to clones recovered from marine environment rather than culture species, suggesting that more effort to isolate dominant prokaryotes should be madeto understand physiological traits of them. Ordination analysis of the prokaryotic community revealed that temporal and spatial diversity of prokaryotic communities were mainly influenced by temperature and depth in the East Sea.chnique. The investigations were conducted four times between 2007 and 2009 and water samples were obtained from 0 m, 50 m, 200 m and 700-800 m depths in coastal and offshore stations. The prokaryotic abundance, leucine incorporation rate and other environmental parameters were also measured. By PCR-DGGE-sequencing approach, we obtained 284 bacterial sequences and 166 archaeal sequences, respectively.The most frequently detected phylotypes were Alpha-proteobacteria, Gamma-proteobacteria, Bacteroidetes, Cyanobacteria, and Euryarchaeota. Actinobacteria, and Thaumarchaeota were occasionally detected. Most of the phylotypes were more closely related to clones recovered from marine environment rather than culture species, suggesting that more effort to isolate dominant prokaryotes should be madeto understand physiological traits of them. Ordination analysis of the prokaryotic community revealed that temporal and spatial diversity of prokaryotic communities were mainly influenced by temperature and depth in the East Sea.