Submitted to: American Chemical Society North Eastern Regional Meeting
Publication Type: Proceedings
Publication Acceptance Date: 2/14/1998
Publication Date: N/A
Interpretive Summary: This is a paper which will be given at the 16th North American Symbiotic Nitrogen Fixation Congress. An outline is given about technical definitions of taxonomy and the evolutionary biology of bacteria. Approaches for estimating evolutionary relationships among bacteria which form symbiotic nitrogen-fixing symbioses sConclusions are made that estimates of evolutionary relationships could well be compromised by multiple copies of genes and recombination between copies which have different sequences. In this context, the evolutionary relationship of strains from Medicago species under study in our laboratory do not adhere to those of type strains usually forming symbioses with these host plants. The possibility is advanced that recombination events may have occurred in genes of the type strains which have affected the estimated genetic relationship. Also outlined are two methods by which bacteria are grouped together. We demonstrate that the interpretation of results from these approaches are subjective and that results from both methods are needed when groupings are made. This information will be useful to scientists at the meeting who are interested in taxonomy and strain identification.
Technical Abstract: This is not required.