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A marine bacterial strain, designated FR1311 T , was isolated from a sea-water sample from Ganghwa Island, South Korea. Cells were Gram-negative, facultatively anaerobic, catalase-and oxidase-positive, motile, oval or rod-shaped and halophilic (optimum sea-salt concentration for growth of 5-6 %). Phylogenetic analysis of its 16S rRNA gene sequence revealed that it represented a distinct line of descent within the genus Photobacterium. The major fatty acids were straight-chain saturated (C 16 : 0 ) and monounsaturated fatty acids (C 16 : 1 v7c and C 18 : 1 v7c). The predominant respiratory lipoquinone was Q-8. The DNA G+C content was 44 mol%. The phenotypic features of strain FR1199 T were similar to those of Photobacterium damselae subsp. damselae and Photobacterium damselae subsp. piscicida, but several physiological and chemotaxonomic properties readily distinguish the new isolate from them. On the basis of the polyphasic results revealed in this study, FR1311 T is considered to be the type strain of a novel species, for which the name Photobacterium ganghwense sp. nov. is proposed. The type strain is FR1311 T (=IMSNU 60287 T =KCTC 12328 T =JCM 12487 T ).

A bacterial isolate, tentatively named SK-3, was isolated from tertiary lagoon sludge contaminated with polychlorinated biphenyls for over 25 years. SK-3 was able to grow on 2-chlorobiphenyl, 3-chlorobiphenyl, 4-chlorobiphenyl (4-CB), chloroacetate and 4-chlorobenzoic acid (4-CBA) as sole carbon and energy sources. During growth on 4-CB, a stoichiometric amount of chloride ion was produced and growth yields were comparable to those observed during growth on biphenyl. The production of 4-CBA as a metabolite was not observed. Protein yields during growth on 4-CB and biphenyl suggested that the presence of the chlorine did not impede use of carbons on both aromatic rings. Growth on 4-CBA also resulted in nearly stoichiometric production of chloride ion. Benzoate-grown SK-3 was also able to degrade several Aroclor 1242 congeners without the need for a primary substrate of previous growth on biphenyl.

Rates of anaerobic transformation of carbon tetrachloride (CT) by the facultative anaerobe Shewanella putrefaciens 200 were increased by the presence of Fe(III)-containing minerals. In batch reactors with amorphous, Fe(III)-hydroxide and S. putrefaciens, CT transformation rates could be modeled by a first-order expression in which the pseudo-first-order rate constant was linearly proportional to the initial concentration of Fe(III)-oxide. Subsequent measurement of soluble and acid-extractable Fe(II) showed that increased CT transformation rates were proportional to microbially reduced, surface-bound Fe(II), rather than soluble Fe(II). In biomimetic experiments using 20 mM dithiothreitol (DTT) as a reductant, rates of transformation of CT by DTT were low in the absence of Fe(III)-oxides. However, in the presence of iron oxides, DTT was able to transform CT at elevated rates. Results again strongly suggested that surface-bound Fe(II) was primarily responsible for the reductive transformation of CT. Results suggested that the surface area of the iron mineral determines the rate of CT transformation by affecting the extent of iron reduction. Chloroform (CF) was the only transformation product identified and production of CF was nonstoichiometric. In microbial and abiotic experiments with Fe(III) oxides, the percentage of the transformed CT recovered as CF decreased even though the rate and extent of CT transformation was increased. Overall, our results have important implications for an improved understanding of possible microbial and geochemical interactions in the environmental transformation of chlorinated organic pollutants and for modeling of CT transformation rates in anaerobic, iron-bearing sediments.