Fine Structure of Methane and Other Hydrocarbon-utilizing Bacteria

Abstract

S U M M A R YMethane-utilizing bacteria were examined by electron microscopy and found to possess complex membranous structures within the cytoplasm. Two types of membrane organization were recognized. One type consisted of pairs of membranes which either extended throughout the organism or were arranged at the periphery where they ran parallel to the cytoplasmic membrane. The other type consisted of vesicular discs of membrane organized into bundles which were distributed throughout the organism. Bacteria utilizing C, to C4 gaseous n-alkanes and C,, to C,, liquid n-alkane mixture did not possess such extensive membranous structures. The former contained membranous bodies of the mesosome type, whilst the latter possessed only a cytoplasmic membrane. These structural differences add to the growing list of properties separating CH,-utilizing bacteria from those utilizing C, and higher n-alkanes.

Carbon monoxide‐stimulated respiration in methane‐utilizing bacteria

“…These results suggest that although methane and CO may both be oxygenated by a mono-oxygenase in M. trichosporium OB3B, as in I? methanica, there may be some differences between the oxidative pathways of these methylotrophs consistent with differences between their membrane structures [3] and carbon assimilation pathways [4]. Further work is needed to clarify this point.…”

“…It is the purpose of this communication to demonstrate that CO, a compound that does not support the growth of methylotrophs, can however be oxidised by these organisms. Whole-cell suspensions of Pseudomonas methanica and Methylosinus trichosporium OB3B, members of classes of methylotrophs that differ in their internal membrane structure [3] and their pathways sf one-carbon assimilation [4], are both capable of COstimulated respiration. Results of work with cell-free extracts of P. methanica capable of methane plus NADH-dependent or CO plus NADR dependent respiration and methane-or CO-dependent NADH oxidation indicate that a mono-oxygenase-type mechanism is involved in both methane and CO oxidation.…”

A New, Mushroom-shaped Budding Bacterium

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A mushroom-shaped budding bacterium, isolated from fresh pond water, is unlike any previously described aquatic budding bacteria (Whittenbury & McLee, I 967 ; Hirsch & Rheinheimer, 1968 ; Staley, 1968). Its morphological 'life-cycle' and other properties are described.

METHODS

Media.

The organism was grown routinely in glucose-salts medium (pH 6.9) of the following composition: (NH4)2S04, 0.1 % (w/v); NaCI, 0.05 % (w/v); MgS04, 7H20, 0.05 % (w/v); NaH2P04, 12H20, 0.07 % (w/v); NaH,PO,, 2H20, 0.03 % ( Substrate utilization.

…”

“…A mushroom-shaped budding bacterium, isolated from fresh pond water, is unlike any previously described aquatic budding bacteria (Whittenbury & McLee, I 967 ; Hirsch & Rheinheimer, 1968 ; Staley, 1968). Its morphological 'life-cycle' and other properties are described.…”

Cytochromes of two methane‐utilizing bacteria

“…The two organisms selected for this study, Methylomonas albus and Methylosinus trichosporium, represent two groups of methylotrophs which have previously been shown to differ with respect to the structural organisation of their cytoplasmic membranes [1 ] and pathways of methane assimilation [2]. This report describes the spectrophotometric examination of the cytochromes present in these two bacteria and discusses the possible involvement of a carbon monoxide-sensitive cytochrome in the early stage(s) of methane oxidation.…”