Cystis and Nostoc at 8.4 (28.1 ) and 9.8 (36.1 ), respectively. Another possible influence on the expansion is the presence of duplicate copies of recA, an important multifunctional DNA repair and recombination enzyme found in nearly every organism (reviewed in ref. 22). There are an astounding seven distinct copies of this gene (recA) found in the A. marina genome, far greater than the previous