Autotrophic growth on carbon disulfide is a property of novel strains of Paracoccus denitrificans

Abstract

Three distinct strains (KL1, KS1, and KS2) of facultatively chemolitho-autotrophic bacteria able to use carbon disulfide or carbonyl sulfide as sole energy substrates were identified as novel strains of Paracoccus denitrificans. Evidence for their identity as biovars of P. denitrificans and as close relatives of Paracoccus versutus is based on their DNA composition, total sequencing of the genes for their 16S rRNA, muropeptide profiles, amino acid composition of peptidoglycan, kinetics of murein degradation by lysozyme, possession of large plasmids (91-98 kb) and megaplasmids (> 450 kb), and plasmid transfer between the strains and with P. denitrificans and P. versutus. No functions have been identified for the 91- to 98-kb plasmids of strains KL1 and KS2, but curing strain KL1 of its plasmid did not affect growth on carbon disulfide, thiosulfate or succinate. Emendation of the formal description of Paracoccus denitrificans is presented. Autotrophic growth on carbon disulfide and thiosulfate was confirmed by 14CO2 fixation. Evidence is presented for initiation of carbon disulfide oxidation by an NADH-dependent oxygenase. Cell-free extracts catalyzed (1) NADH-stimulated uptake of oxygen in the presence of carbon disulfide, and (2) carbon-disulfide-stimulated oxidation of NADH. The activity was not sedimented at 50,000 x g. Intermediates in aerobic carbon disulfide metabolism were shown by GC and GC/MS to include carbonyl sulfide and hydrogen sulfide, but anaerobic production of COS and H2S from carbon disulfide did not occur. SDS-PAGE of cell-free extracts showed polypeptides that were unique to growth on carbon disulfide, common to carbon disulfide and carbonyl sulfide, or found after growth on carbon disulfide, carbonyl sulfide or thiosulfate. The possible identity of these as proteins involved in sulfur compound metabolism is discussed.

A re-evaluation of the taxonomy of Paracoccus denitrificans and a proposal for the combination Paracoccus pantotrophus comb. nov.

“…This conclusion was also drawn by Goodhew et al (1996), who pointed out that the 'Stanier strain 381 ' cannot have given rise to both ATCC 17741T and DSM 65, as stated in the respective culture collection catalogues. The group B sequence was also identical to that reported for P. denitrykans strain LMG 4218 (sequence X69159) and for T. (Ludwig et al, 1993), and showed > 99 % similarity to the three carbon-disulfideusing strains recently classified as P. denitrzjicans DSM 11072, DSM 11073 and DSM 11104 (Jordan et al, 1997). The similarity between members of groups A and B was 98-1 YO in all cases.…”

“…Beijerinck 1910), with other extant examples of the original isolate being LMD (Delft Collection of Microorganisms, Delft, The Netherlands) 22.2 lT, ATCC 19367 and ATCC 13543 (Davis et al, 1969). Numerous similar isolates were subsequently assigned to P. denitrificans, which became recognized as a heterogeneous species comprising several biotypes (Jordan et al, 1997;Van Verseveld & Stouthamer, 1992). A related single-species genus, Thiosphaera pantotropha (Robertson & Kuenen, 1983), was also assigned to P. denitrijicans on the basis of analysis of the base sequence of the 16s rRNA gene (Ludwig et al, 1993).…”

“…Recently, the history of the strains in culture 00886 0 1999 IUMS Y17512 Y17511 U580 17 U58015 U58016 Y16933 Y 16934 X69159 D32243 Y 16932 Y16931 D32242 D32241 D42239 D32238 D32240 YO7705 collections in relation to the sources of the original isolates was examined by comparative analysis of their c-type cytochrome and protein profiles, and the case for the reclassification of these strains into more than one species was considered (Goodhew et al, 1996). Using 16s rRNA sequence analysis, three new isolates of carbon-disulfide-using facultative chemolithotrophs were assigned to P. denitriJicans (Jordan et al, 1995(Jordan et al, , 1997. This classification, like those used by Ludwig et al (1993) in classifying T. pantotropha, as well as for our and Urakami's descriptions of several new Paracoccus species (Katayama et al, 1995;Ohara et al, 1990;Urakami et al, 1989Urakami et al, , 1990, relied on the 16s rRNA sequence reported by Ludwig et al (1 993) for P. denitrzjicans LMG (Ghent Collection of Microorganisms, Ghent, Belgium) 421 8, supposedly a derivative of the type strain.…”

Redefining Paracoccus denitrificans and Paracoccus pantotrophus and the case for a reassessment of the strains held by international culture collections

“…denitrificans' appeared only in the seventh edition (Breed et al, 1957). For many years, P. denitrificans remained the only authentic species of Paracoccus, with the result that biotypes actually differing from each other at the species level were assigned to this species (Baj, 2000;Dobson & Franzmann, 1996;Kelly et al, 2000;Jordan et al, 1997;Nokhal & Schlegel, 1983;Van Verseveld & Stouthamer, 1992). An example was Thiosphaera pantotropha (strain GB17…”

“…(Kelly & Wood, 1982;Kelly et al, 2000;Taylor & Hoare, 1969). Moreover, the ability to grow on carbon disulfide is a property of P. pantotrophus, not yet shown also to apply to P. denitrificans (Jordan et al, 1995(Jordan et al, , 1997Rainey et al, 1999).…”