Pseudomonas pseudoflava, a New Species of Hydrogen-Oxidizing Bacteria: Its Differentiation from Pseudomonas flava and Other Yellow-Pigmented, Gram-Negative, Hydrogen-Oxidizing Species

Abstract

Five new strains of yellow-pigmented, gram-negative, motile, hydrogen-oxidizing bacteria were isolated; each served as a host for simultaneously isolated bacteriophages. These isolates and two additional strains were compared with other gram-negative, hydrogen-oxidizing bacteria with respect to morphology; nutritional and biochemical properties; growth parameters; cytochrome content; pigment production; susceptibility to bacteriophages, bacteriostatic agents, and antibiotics; deoxyribonucleic acid base composition; and deoxyribonucleic aciddeoxyribonucleic acid homology. Six of the strains were characterized by a high degree of interstrain similarity and were found to be related to Pseudomonas flaua. However, due to basic differences between these strains and P. fZaua, the former are regarded as comprising a new species for which, because of its moderate relationship to P. flava, the name Pseudomonas pseudoflava is proposed. The type strain of P. pseudoflava, GA3, has been deposited with the Deutsche Sammlung von Mikroorganismen in Gottingen under the number DSM 1034.The facultatively autotrophic hydrogen-oxidizing bacteria-commonly called hydrogen bacteria-are a taxonomically heterogeneous group among the chemolithoautotrophs. Their physiology has recently been reviewed by Schlegel (30). In the summer and autumn of 1973, about 80 strains of hydrogen bacteria were isolated and tested for ability to serve as hosts for simultaneously isolated bacteriophages. Among these, only a few strains of polarly flagellated bacteria forming yellow colonies were found to be susceptible to the bacteriophages. These host bacteria had a high interstrain similarity and were considered to be related to Pseudomonas flaua (15).Further studies were aimed at characterizing the six host bacteria, evaluating their similarity and delineating them from other yellow-pigmented hydrogen bacteria, and determining their taxonomic niche. For direct comparison with these strains, several type strains and some other strains of hydrogen bacteria, especially the yellow-pigmented ones, were included in this study. Morphological features; nutritional and biochemical properties; growth parameters; the cytochromes; pigmentation; and susceptibility to bacteriophages, bacteriostatic agents, and antibiotics were investigated. In addition, the serological relationships to other gram-negative hydrogen bacteria and the deoxyribonucleic acid (DNA) base compositions and DNA-DNA homologies of these strains were studied.As a result of these studies, it was concluded that the six new isolates belong to a new species, for which we propose the name Pseudomonas pseudoflava (pseu.do

Hydrogenophaga, a New Genus of Hydrogen-Oxidizing Bacteria That Includes Hydrogenophaga flava comb. nov. (Formerly Pseudomonas flava), Hydrogenophaga palleronii (Formerly Pseudomonas palleronii), Hydrogenophaga pseudoflava (Formerly Pseudomonas pseudoflava and "Pseudomonas carboxydoflava"), and Hydrogenophaga taeniospiralis (Formerly Pseudomonas taeniospiralis)

“…Motile by means of one, rarely two, polar to subpolar flagella. (4,48). Nutritional and enzymatic features are listed in Table 7.…”

“…Recently, Jenni et al (21) reported nitrogen fixation for a strain (strain NEU 2226) which they assigned to [Pseudornonus] pseudoJava, although this feature could not be detected in strain GA3T. Hydrogenophaga pseudoflava was isolated from soil, mud, and water by enrichment for hydrogen bacteria (4,33). The mean G+C content of the DNA is 66 to 69 mol%.…”

Characterization and Comparison of the DNAs of the Three Closely Related Bacteriophages gd, ge and gf with the Genome DNA of the Hydrogen-oxidizing Host Strain Pseudomonas pseudoflava GA3

“…5) and with HindIII restriction enzyme. Taken together with the data on the properties of the bacteriophage protein coats and on their biological relatedness (Auling, 1978;Auling et al I977), one can conclude that the three P. pseudoflava bacteriophages gd, ge and gfare identical.…”

Pseudomonas taeniospiralis sp. nov., an R-Body-Containing Hydrogen Bacterium

“…strain 2K1 has been described previously (12, 13), and a culture of this strain was deposited with the Deutsche Sammlung von Mikroorganismen, Gottingen, Federal Republic of Germany, under the number DSM 2082. Pseudornonus p s e u d o j a w GA3 (= DSM 1034) (2) The basal medium used for growth was the mineral medium described by Schlegel et al (20). One milliliter of trace elements solution SL6 of Pfennig (17) concentrated 10-fold was added to 1 ml of medium.…”

“…DNA-DNA reassociation was performed as previously described (2), and the degree of binding was calculated by using the formula of DeLey et al (7).…”