Sobecky, P. A.. Georgia Institute of Technology, patricia.sobecky@biology.gatech.edu
Cain, C. A.. Georgia Institute of Technology, cc165@prism.gatech.edu
Bellamy, M. Georgia Institute of Technology, gtd75a@prism.gatech.edu

 
MOLECULAR ASSESSMENT OF PLASMID DIVERSITY IN MARINE MICROBIAL COMMUNITIES
 
The remarkable array of marine microbial diversity being revealed by nucleic acid-based methods such as 16S rRNA phylogenetic analysis continues to indicate the presence of novel and as yet uncharacterized microbial types. The considerable biodiversity currently being detected in marine systems has now also been extended to plasmid populations occurring in marine sediment microbial communities. To assess the molecular diversity of plasmids occurring in marine bacterial assemblages, we have developed a replicon rescue approach using Escherichia coli as the host background. To date, seven different replication-proficient fragments (1.8- to 2.3-kb) have been isolated from plasmids ranging in size from <10-kb to 30-kb. Four of the fragments have been sequenced, analyzed and found to contain features common to replication origins of well-characterized plasmids from clinical bacterial isolates, suggesting that there may be similar mechanisms for plasmid replication in the indigenous plasmids of gram-negative marine sediment bacteria. Using this collection of environmental-based replicon probes, results will be presented that indicate the diversity of plasmids in marine environments is greater than anticipated and that a molecular-based typing and identification system based on replication and incompatibility regions of plasmids occurring in marine bacteria is valuable.
 
Day: Tuesday, Feb. 2
Time: 09:15 - 09:30am
Location: Hilton of Santa Fe
 
Code: SS40TU0915H