DNA relatedness of oil-field isolates of Shewanella putrefaciens

Abstract

Classification of several oil-field isolates of Shewanella putrefaciens was assessed by nucleic acid hybridization techniques. The results of DNA-DNA hybridization analysis generally confirmed the phenetic characterization of these isolates and supported the classification of oil-field isolates of S. putrefaciens groups 1, 3 and 4. However, two group 2 isolates were considered to be mistakenly classified. Strain ESSO 1-1 appeared to belong to group 3, a result which was supported by the pattern of 5S rRNA hybridization to restriction digests of genomic DNA, and strain 213 appeared to be a member of group 1. Several of the oil-field strains of S. putrefaciens were found to possess indigenous plasmids, a feature which was not shared by the other strains of S. putrefaciens examined. This study indicates that these oil-field isolates were more closely related to strains of S. putrefaciens isolated from various environments than to the other Shewanella species (S. benthica and S. hanedai) that shared the important metabolic characteristics of iron reduction and sulfide production from thiosulfate. There was very little genetic relationship found between Shewanella spp. and the other species studied.