Transformation in Bacillus subtilis: purification and partial characterization of a membrane-bound DNA-binding protein.

AUTOR(ES)

Smith, H

RESUMO

In DNA binding-deficient mutants of Bacillus subtilis a competence-specific protein with a subunit molecular weight of 18,000 was absent. The native protein containing this subunit was purified from B. subtilis membranes by chromatography on hydroxyapatite, DEAE-cellulose, and Sephacryl S-200. This protein appeared to be complexed with a second protein of slightly lower molecular weight (17,000) and a different isoelectric point. The native protein complex (apparent molecular weight, 75,000) contained approximately equal amounts of the two polypeptides and showed a strong DNA-binding activity. Incubation of the complex with plasmid and bacteriophage DNA revealed nuclease activity, specifically directed toward double-stranded DNA. Predominantly single-stranded nicks and a limited number of double-stranded breaks were introduced in the presence of Mg2+ ions. In the presence of Mn2+ ions the complex produced low-molecular-weight breakdown products from the DNA.

Documentos Relacionados

• Amplification of a major membrane-bound DNA sequence of Bacillus subtilis.
• Extracellular and membrane-bound proteases from Bacillus subtilis.
• Purification and characterization of extracellular soluble and membrane-bound insoluble alkaline phosphatases possessing phosphodiesterase activities in Bacillus subtilis.
• Purification and molecular characterization of adenovirus type 2 DNA-binding protein.
• DNA-binding proteins of Haemophilus influenzae: purification and characterization of a major intracellular binding protein.