Membrane proteins from Bacillus megaterium KM

Paracrystalline Sheets Reaggregated from Solubilized Exosporium of Bacillus cereus

“…Proc., p. 51, 1970). Mirsky (17) has reported that a protein fraction from SDS-solubilized protoplast membranes of B. megaterium strain KM, after elec- tracings of polyacrylamide gels after disc electrophoresis of the supernatant fraction from phenol-solubilized (A) and SDS-solubilized (B) exosporium. The broken line in (B) indicates the projected extension of the second band of protein, which was masked by the diffusion ofdye.…”

“…Considerable information is available about the solubilization and reaggregation of cytoplasmic membrane, from Mycoplasma (5,21,23) and bacterial protoplasts (4,17), and these studies provided directly useful precedents for studying the molecular organization of exosporium. Among the several proposed models of membrane structure (13), the subunit model of Green et al (10) postulates that membranes typically may be comprised of cuboidal repeating units formed in vivo through self-assembly into a two-dimensional sheet.…”

Conservation and transformation of energy by bacterial membranes.

“…In this connection, it is worth stressing that analysis of the proteins of bacterial membranes by gel electrophoresis reveals several dozen components but no single, major constituent to correspond to the expectation of a "structural protein" (71,254,324,330,331, but also 302). The evidence on which the concept of a structural protein in mitochondrial membranes was originally based is now known to be faulty (reviews: 197, 310); proteins whose sole function is structural may well exist in membranes, but the idea now has little experimental foundation.…”

Membrane and nonmembrane proteins of mammalian cells. Synthesis, turnover, and size distribution

“…Schnaitman (1969), using techniques similar to ours with rat liver cells, found 23 different proteins comprising the inner mitochondrial membrane, 12 species in the outer mitochondrial membrane, and 15 proteins each in the smooth and rough microsomal membranes. Finally, the plasma membrane of B. megaterium was shown to contain at least 12 different proteins (Mirsky, 1969).…”