Spanin function requires subunit homodimerization through intermolecular disulfide bonds.

ABSTRACT: The λ Rz and Rz1 proteins are the subunits of the spanin complex, required for the disruption of the outer membrane during host lysis. Rz, the inner membrane or i-spanin, has a largely alpha-helical periplasmic domain, whereas Rz1, the outer membrane or o-spanin, has a 25% proline content with no predicted secondary structure. We report that both Rz and Rz1 accumulate as homodimers covalently linked by intermolecular disulfide bonds involving all three Cys residues, two in Rz and one in Rz1. Moreover, of these three intermolecular disulfides, spanin function requires the presence of at least one of the two linkages nearest the Rz-Rz1 C-terminal interaction domains; i.e. either the Rz1-Rz1 disulfide or the distal Rz-Rz disulfide link. In a dsbC host, but not in dsbA or dsbA dsbC hosts, form

SUBMITTER: Berry JD 

PROVIDER: S-EPMC3612274 | biostudies-literature | 2013 Apr

REPOSITORIES: biostudies-literature