16S rRNA gene-based molecular analyses revealed the presence of several large and so far uncultivated clades within class γ-Proteobacteria, designated γ-proteobacterial marine sediment (GMS) clades 1 to 4, in marine sediment. The GMS clades appear only indigenous to marine sediment and so far have an unknown functionality. SYBR Green-based real-time PCR analyses using GMS clade-specific primers indicated GMS clades were a significant part of the bacterial community (0.3-8.7% of total 16S rRNA genes) in both polar and temperate marine sediment samples. Univariate statistical analyses indicated that GMS clade communities were indistinguishable in two temperate coastal sediment samples even though these possessed very different mean grain sizes, organic contents, and organic loading rates. GMS clade communities were slightly different (p < 0.05) between polar and temperate sites, suggesting that psychrophilic adaptation among GMS clade taxa corresponds only to subtle phylogenetic differences. Similar levels of difference were also observed through a sediment core reflecting that through the sediment core history, which spanned ∼3000 years, GMS clonal diversity shifted only marginally. © Springer Science+Business Media, Inc. 2005.

Item Type:	Refereed Article
Research Division:	Biological Sciences
Research Group:	Microbiology
Research Field:	Microbial ecology
Objective Division:	Environmental Management
Objective Group:	Other environmental management
Objective Field:	Other environmental management not elsewhere classified
UTAS Author:	Bowman, JP (Associate Professor John Bowman)
UTAS Author:	McCammon, SA (Ms Sharee McCammon)
UTAS Author:	Dann, AL (Dr Alison Dann)
ID Code:	35089
Year Published:	2005
Web of Science® Times Cited:	31
Deposited By:	Agricultural Science
Deposited On:	2005-08-01
Last Modified:	2007-11-09
Downloads:	0