YpeB is a sporulation protein that, together with the spore-cortex-lytic enzyme SleB, is required for normal germination. YpeB stabilises SleB enzyme and may regulate its activity during spore germination [1-6]. It consists of three tandemly repeated PepSY domains at the C-terminal, being the first two (PepSY1 and PepSY2) represented in this entry and the last one in Pfam:PF03413.

1: Complete spore-cortex hydrolysis during germination of Bacillus subtilis 168 requires SleB and YpeB. Boland FM, Atrih A, Chirakkal H, Foster SJ, Moir A; Microbiology 2000;146:57-64. PMID:10658652

2: Two class A high-molecular-weight penicillin-binding proteins of Bacillus subtilis play redundant roles in sporulation. McPherson DC, Driks A, Popham DL; J Bacteriol. 2001;183:6046-6053. PMID:11567005

3: Role of membrane-bound thiol-disulfide oxidoreductases in endospore-forming bacteria. Moller M, Hederstedt L; Antioxid Redox Signal. 2006;8:823-833. PMID:16771673

4: Subcellular localization of a germiantion-specific cortex-lytic enzyme, SleB, of Bacilli during sporulation. Masayama A, Fukuoka H, Kato S, Yoshimura T, Moriyama M, Moriyama R; Genes Genet Syst. 2006;81:163-169. PMID:16905870

5: Germination of spores of Bacillales and Clostridiales species: mechanisms and proteins involved. Paredes-Sabja D, Setlow P, Sarker MR; Trends Microbiol. 2011;19:85-94. PMID:21112786

6: Crystal structure of the PepSY-containing domain of the YpeB protein involved in germination of bacillus spores. Ustok F, Chirgadze D, Christie G. Proteins. 2015;83(10):1914-21 PMID:26219275