Fine structure of methane and other hydrocarbon-utilizing bacteria.

Abstract

SUMMARY Methane-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 C2 to C4 gaseous n-alkanes and C11 to C18 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 CH4-utilizing bacteria from those utilizing C2 and higher n-alkanes.