Folia Microbiologica

, 49:679

Identification of a holin encoded by theStreptomyces aureofaciens phage µ1/6; functional analysis inEscherichia coli system


DOI: 10.1007/BF02931549

Cite this article as:
Farkašovská, J., Godány, A. & Vlček, C. Folia Microbiol (2004) 49: 679. doi:10.1007/BF02931549


An open reading frame encoding an 88 amino acid protein was present downstream of the previously characterized endolysin ofStreptomyces aureofaciens phage µ1/6. Structural analysis of its sequence revealed features characteristic for holin. This open reading frame encoding the putative holin was amplified by polymerase chain reaction and cloned into the expression vector pET-21d(+). Synthesis of the holin-like protein resulted in bacterial cell death but not lysis. Theholµ1/6 gene was able to complement the defective λS allele in the nonsuppressingEscherichia coli HB101 strain to produce phage progeny. This fact suggests that the proteins encoded by both phage genes have analogous function,i.e. the streptomycete holin induces nonspecific lesions in the cytoplasmic membrane, through which the λ endolysin gains an access to its substrate, the cell wall. The concomitant expression of bothS. aureofaciens holµ1/6 and λ endolysin inE. coli resulted in abrupt cell lysis. This result provided further evidence that the product ofholµ1/6 gene is a holin.

Copyright information

© Institute of Microbiology, Academy of Sciences of the Czech Republic 2004

Authors and Affiliations

  1. 1.Institute of Molecular BiologySlovak Academy of SciencesBratislavaSlovakia
  2. 2.Center for Integrated Genomics, Institute of Molecular GeneticsAcademy of Sciences of the Czech RepublicPragueCzechia