Genetic analysis of the folding pathway for the tail spike protein of phage P22.

AUTOR(ES)

Goldenberg, D P

RESUMO

Temperature-sensitive mutations in the gene encoding the trimeric tail spike protein of phage P22 interfere with protein maturation at 39 degrees C. We show here that temperature-sensitive mutations at many sites block the folding pathway prior to accumulation of the partially folded protrimer intermediate. Temperature-shift experiments indicate that at least some of the mutants accumulate an earlier intermediate in the folding pathway. Immunoprecipitation experiments suggest that the conformation of the isolated temperature-sensitive polypeptide chains is closer to that of the unfolded chain than to that of the mature spike formed at permissive temperature. The sites of these mutations probably represent amino acid sequences that play key roles during the folding of the tail spike polypeptide chain but are not important in the mature protein.

Documentos Relacionados

• Single amino acid substitutions influencing the folding pathway of the phage P22 tail spike endorhamnosidase.
• Trimeric intermediate in the in vivo folding and subunit assembly of the tail spike endorhamnosidase of bacteriophage P22.
• Fine Structure Genetic and Physical Map of the Phage P22 Tail Protein Gene
• Sonic fragility of the head-tail bond of bacteriophage P22.
• Genetic Properties of Temperature-Sensitive Folding Mutants of the Coat Protein of Phage P22