HALOPHILIC BACTERIA.
Abstract
Ornithine Carbamoyl Transferase from Halobacterium salinarium has been purified. This enzyme is irreversibly inactivated in the absence of salt and the whole purification procedure, preparation of cell-free extracts, acetone fractionation, gel filtration, sucrose gradient centrifugation and chromatography on calcium phosphate gel was carried out in the presence of 4.3 M NaCl. The enzymatic properties of the purified Ornithine Carbamoyl Transferase were studied and compared to those of Ornithine Carbamoyl Transferase from non-halophilic organisms. The halophilic enzyme is composed of subunits with a molecular weight of about 75,000. Prolonged dialysis against NaCl free media resulted in a drastic decrease of the sedimentation velocity for the protein. The enzyme contains high relative concentrations of acidic amino acids; Flagella from Halobacteria have a marked tendency to aggregate in spiral structures visible with the light microscope. A method for staining the flagella has been developed. All Halobacteria isolated to date have complex nutritional requirements. A method for isolating Halobacteria with simple growth requirements is described. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 30, 1970
- Accession Number
- AD0712844
Entities
People
- Ian E. D. Dundas
Organizations
- University of Bergen