Accession Number : AD0451606

Title :   THE RIBOSOMES OF THE EXTREMELY HALOPHILIC BACTERIUM, HALOBACTERIUM CUTIRUBRUM,

Corporate Author : NATIONAL RESEARCH COUNCIL OF CANADA OTTAWA (ONTARIO) DIV OF BIOSCIENCES

Personal Author(s) : Bayley,S. T. ; Kushner,D. J.

Report Date : 17 MAR 1964

Pagination or Media Count : 18

Abstract : The ribosomes of Halobacterium cutirubrum, a micro-organism that grows in saturated sodium chloride and probably has an internal concentration of potassium chloride near saturation, exist as 70 s particles when isolated in saturated potassium chloride containing 0.1 m-magnesium chloride at pH7. These particles are stable in concentrations of magnesium ions as high as 0.4 m. If the potassium ion concentration is below about 4 m, or the magnesium ion concentration below 0.1 m, the ribosomes dissociate into 52 s and 31 s subunits. The requirement by the 70 s particles for potassium ions is specific; in high concentrations of ammonium or caesium ions, many of the ribosomes dissociate into subunits, while in high concentrations of sodium ions, they dissociate and aggregate in a complex way. About 53% of the RNA of the cell is accounted for by the ribosomes, which consist of 60% RNA and 40% protein. The estimated molecular weights of the ribosomes and its subunits are in the ratio 3 : 2 : 1. (Author)

Descriptors :   (*BACTERIA, RIBOSOMES), (*RIBOSOMES, BACTERIA), BIOASSAY, STABILITY, IONS, CULTURE MEDIA, POTASSIUM, MAGNESIUM, DISSOCIATION, BIOCHEMISTRY, CHEMICAL ANALYSIS, MOLECULAR PROPERTIES, SALTS, CHLORIDES, SODIUM COMPOUNDS, POTASSIUM COMPOUNDS

Distribution Statement : APPROVED FOR PUBLIC RELEASE