Covalent Linkage of Polyamines to Peptidoglycan in Anaerovibrio lipolytica

Abstract

ABSTRACT Spermidine and cadaverine were found to be constituents of the cell wall peptidoglycan of Anaerovibrio lipolytica , a strictly anaerobic bacterium. The peptidoglycan was degraded with the N -acetylmuramyl- l -alanine amidase and endopeptidase into two peptide fragments, peptide I and peptide II, at a molar ratio of 4:1. Peptides I and II were identified as l -alanine– d -glutamic acid( α cadaverine) γ meso -diaminopimelic acid (DAP)– d -alanine and l -alanine– d -glutamic acid( α spermidine) γ meso -DAP– d -alanine, respectively. The N 1 -amino group of spermidine was linked to the α-carboxyl group of the d -glutamic acid residue of peptide II.