The Localization of Cytochromes and Carotenoids in Isolated Bacterial Membranes and Envelopes

Abstract

Summary. Examination of oxidized and reduced spectra of isolated membranes (plasma and mesosome membranes) and protoplasmic fractions of the lysozymesensitive Cram-positive bacteria Bacillus Ucheniformk, Bacillus stearothcrmophilus, Micrococcus lysodeikticus and Sarcina lutea, has shown that virtually all of the cytochrome and in addition the carotenoids in the latter two organisms are localized in tbe membranes. Although the membranes isolated from cells of Micrococcus lysodeikticus and Sarcma lutea grown in the presence of diphenylamine still possessed the normal complement tif eytochromes bound to the membranes, the structures were devoid of the unsaturated carotenoids. "Walls" or "envelopes" of Escherichia coli contained a higher proportion of the eytochromes and NADH oxidase aetivity than that fount! in the protoplasm. NADH oxidase activity was also localized in isolated membrane structures of the other bacteria investigated.INTRODUCTION.

The Bacterial Membrane

“…The localization of other "lipid-soluble" components of the bacterial cell, including carotenoids and menaquinones, has been reported in a number of studies (Matthews and Sistrom, 1959;Salton and Ehtisham-ud-din, 1965;Bishop and King, 1962;Salton and Schmitt, 1967a). The carotenoid pigments have been particularly useful "lipid markers" in studies of membrane isolation, fractionation, and characterization (Salton, 1967b).…”

The major carotenoid pigment of a psychrotrophic Micrococcus roseus strain: purification, structure, and interaction with synthetic membranes

“…In fact, cells of M. roseus in which carotenoid biosynthesis was stopped with diphenylamine showed very small amounts of carotenoids but exhibited greater resistance to photodynamic killing than did the pigmented wild-type M. roseus. However, considering that carotenoids are generally associated with either the cell membrane (26) or the cell wall (4,42,44), these pigments may by their interactions alter these structures. Earlier studies demonstrated that the M. roseus cell wall consists of polysaccharides (with galactosamine as the amino sugar), lipids, amino acids, and a peptidoglycan consisting of lysine and alanine (15,32).…”

Isolation and properties of mesosomal membrane fractions from Micrococcus lysodeikticus

“…Release of mesosomal membrane. Convenient marker molecules for membrane fractions of M. lysodeikticus are the carotenoid pigments (see Salton & Ehtisham-ud-din, 1965). The E446 values for carotenoid absorption correlate directly with dry 1972 weight of membrane in suspensions, and as such offer a convenient method for assaying the concentration ofmembrane in aqueous suspensions.…”