A Taxonomic Study of some Gram-negative Facultatively Methylotrophic Bacteria

Abstract

623One hundred and fifty pink-pigmented facultatively methylotrophic bacteria (PPFMs) of the 'Pseudomonas extorquens' type, 28 other facultative methylotrophs and 16 non-methylotrophic marker strains of the genera Pseudomonas, A lcaligenes, Mycoplana and Microcyclus were compared in a numerical phenetic study using 140 unit characters. Data were analysed using the simple matching (SsM) and Jaccard (S,) coefficients and single, complete and average linkage algorithms. Cluster composition was largely the same with each similarity coefficient and linkage method. Four major and seven minor clusters ,containing 187 of the 194 strains were defined above the 80% similarity level. The non-pink methylotrophs were recovered in two major, four minor and two single-membered clusters. One of the major clusters could be equated with Microcyclus aquaticus but strains in the other were not identified. Strains in two of the minor clusters were identified as Pseudomonas species but members of the other two minor and one of the single-strain clusters were not positively identified. They had pseudomonad properties but were not closely associated with any marker strains. The other single-membered methylotroph cluster was thought to be a cytophaga or flexibacter. The remaining minor and single-membered clusters contained only marker strains. All the PPFMs were recovered in the two remaining major clusters which were closely related to each other but not to the rest of the organisms studied. The generic assignment of the PPFMs is discussed and the suggestion is made that the genus Methylobacterium may be the most appropriate place for them, despite their apparentinability to utilize methane.

Antimicrobial Agents and Chemotherapy

“…If several alternative methods are commonly used, it is helpful to identify the method briefly as well as to cite the reference. For example, it is preferable to state "cells were broken by ultrasonic treatment as previously described (9)" rather than "cells were broken as previously described (9)." This allows the reader to assess the method without constant reference to previous publications.…”

“…Agents Chemother. 30: [6][7][8][9][10]1986). Assays that measure the hydrolysis of ␤-lactam antibiotics must be appropriate for the substrate examined (e.g., iodometric methods are not appropriate quantitative assays for substrates whose products are unknown).…”

Classification of Pseudomonas aminovorans and Some Related Methylated Amine Utilizing Bacteria

“…They were shown to form a fairly tight cluster (cluster 1 ; approx 90% similarity level), well separated from the other methylotrophic bacteria and non-methylotrophic reference strains examined (Green & Bousfield, 1982). Since that study it has become apparent that Pseudomonas aminovorans (NCIB 9039), a similar methylated amine utilizing organism, isolated by den Dooren de Jong (1 927) from soil, is phenotypically and morphologically indistinguishable from the seven isolates previously examined (P. N. Green, unpublished data).…”

“…They include a diverse assemblage of organisms (Green & Bousfield, 1981), some of which fit into well recognized taxa. Others, such as the pink-pigmented facultative methylotrophs, have been shown to constitute a new taxon, for which the genus Methylobacterium was subsequently proposed (Patt et al, 1974;Green & Bousfield, 1983).…”

Molecular and Cellular Biology

“…Names of all taxa (kingdoms, phyla, classes, orders, families, genera, species, and subspecies) are printed in italics and should be italicized (or underlined) in the manuscript; strain designations and numbers are not. a Nanomoles of pyruvate formed per milligram of protein in time shown (3,9). b Millimoles of fructose 1,6-diphosphate produced per minute per milligram of protein (7).…”