Organic nutrition of Beggiatoa sp

Abstract

Culture OH-75-B of Beggiatoa sp. differed significantly from any described previously in its utilization of organic carbon and reduced sulfur compounds. It deposited internal sulfur granules characteristic of Beggiatoa sp. with either sulfide or thiosulfate in the medium. This strain (OH-75-B, clone 2a) could be grown in agitated liquid cultures on mineral medium with acetate as the only source of organic carbon. The resultant growth yields and rates were comparable to those for typical heterotrophs. Of the other simple organic compounds tested, only pyruvate, lactate, or ethanol could singly support the growth of this strain. Single sugars or amino acids neither supported growth nor enhanced it when added to acetate-containing medium. In contrast, compounds of the tricarboxylic acid cycle enhanced growth yields when tested in concert with acetate. These and fluoroacetate inhibition results indicate that Beggiatoa sp. possesses a functional tricarboxylic acid cycle. Poor yields characterized the growth of this strain on dilute yeast extract medium, and higher concentrations of yeast extract proved inhibitory. The enzyme catalase, contrary to the findings of others, had no synergistic influence on growth yields when added to medium containing yeast extract or acetate or both.

Use of reduced sulfur compounds by Beggiatoa sp

“…used was OH-75-B subclone 2a (abbreviated, clone 75-2a). The isolation and maintenance of this strain were on a thiosulfate-containing medium with only NTA (nitrilotriacetic acid, a chelator), agar (Difco Laboratories), and organic impurities in agar as possible sources of organic carbon (20). A year after the isolation of OH-75-B, a number of other clones of Beggiatoa sp.…”

“…Many of the experiments used flasks on shakers for determining growth yields and rates as previously described (20). Unless stated otherwise, this replicate flask method was employed for growing inoculation cultures as well as for performing experiments.…”

“…A number of subclones of Beggiatoa (B. cf. keptomitifornis) strain OH-75-B have been isolated which are capable of depositing S0 from either thiosulfate or sulfide (20). This previously undiscovered metabolic flexibility makes it easier to explore the utilization of sulfur in Beggiatoa species.…”

Benthic bacterial diversity from freshwater tufas of the Iberian Range (Spain)

“…The Firmicutes was dominated by Bacillus sp., heterotrophic, aerobic, endospore producers, and one Desulfotomaculum sp., a widespread sulphate‐reducing bacteria (Lin et al ., ). The Gammaproteobacteria were represented by a number of phylotypes: Acidithiobacillus sp., a sulphur–iron oxidizer known from soils and mine drainages (Waksman & Joffe, ); Dokdonella sp., a heterotroph also found in soils (Yoon et al ., ); Lysobacter sp., a genus comprising chitin, starch, cellulose and lignin decomposers, with stringent exoenzymatic capabilities, often harmful for other organisms (Christensen & Cook, ; Roesti et al ., ); Pseudomonas sp., Gram‐negative rods, usually aerobic and capable of degrading a great variety of organic compounds (Madigan et al ., ); Beggiatoa sp., a filamentous sulphide‐oxidizing chemolithotroph, mostly autotroph or mixotroph (see Strohl & Larkin, ; Nelson & Castenholz, ); and Marichromatium sp., an anaerobic, purple sulphur phototrophic bacterium of marine habitats but with close relatives (e.g. Chromatium sp.…”

“…While Beggiatoa sp. can be found in soils and in saline and freshwater settings (Strohl & Larkin, ; Nelson & Castenholz, ), Marichromatium includes only marine species (Serrano et al ., ) which are generally halophilic and alkaliphilic (Swingley et al ., ). It is possible that the DNA sequences found for this type are related to purple bacteria (e.g.…”