Cortical fragment-lytic enzyme (CFLE) is a peptidoglycan hydrolase involved in bacterial endospore germination. CFLE is expressed as an inactive preprotein (called SleB) in the forespore compartment of sporulating cells. SleB translocates across the forespore inner membrane and is deposited as a mature enzyme in the cortex layer of the spore. As part of a sensory mechanism capable of initiating germination, CFLE degrades a spore-specific peptidoglycan constituent called muramic-acid delta-lactam that comprises the outer cortex. CFLE has a C-terminal glycosyl hydrolase family 18 (GH18) catalytic domain as well as two N-terminal LysM peptidoglycan-binding domains. In addition to SleB, this family includes YaaH, YdhD, and YvbX from Bacillus subtilis.

Spore germination protein YaaH [Cell cycle control, cell division, chromosome partitioning].

GH18 domain of an uncharacterized family of bacterial proteins, which share a common three-domain architecture: an N-terminal glycosyl hydrolase family 18 (GH18) domain, a glycosyl transferase family 2 domain, and a C-terminal polysaccharide deacetylase domain.

Chitobiase (also known as di-N-acetylchitobiase) is a lysosomal glycosidase that hydrolyzes the reducing-end N-acetylglucosamine from the chitobiose core of oligosaccharides during the ordered degradation of asparagine-linked glycoproteins in eukaryotes. Chitobiase can only do so if the asparagine that joins the oligosaccharide to protein is previously removed by a glycosylasparaginase. Chitobiase is therefore the final step in the lysosomal degradation of the protein/carbohydrate linkage component of asparagine-linked glycoproteins. The catalytic domain of chitobiase is an eight-stranded alpha/beta barrel fold similar to that of other family 18 glycosyl hydrolases such as hevamine and chitotriosidase.

Glycosyl hydrolases family 18.

Crystalstructure of chitinase from Chromobacterium violaceum ATCC 12472 [Chromobacterium violaceum ATCC 12472]

ChainA, Putative sporulation-specific glycosylase ydhD [Bacillus subtilis subsp. subtilis str. 168],3CZ8_B Chain B, Putative sporulation-specific glycosylase ydhD [Bacillus subtilis subsp. subtilis str. 168]

ChainA, Glycoside hydrolase family 18 [Desulfitobacterium hafniense DCB-2],4WIW_B Chain B, Glycoside hydrolase family 18 [Desulfitobacterium hafniense DCB-2],4WIW_C Chain C, Glycoside hydrolase family 18 [Desulfitobacterium hafniense DCB-2],4WIW_D Chain D, Glycoside hydrolase family 18 [Desulfitobacterium hafniense DCB-2],4WIW_E Chain E, Glycoside hydrolase family 18 [Desulfitobacterium hafniense DCB-2],4WIW_F Chain F, Glycoside hydrolase family 18 [Desulfitobacterium hafniense DCB-2]

Crystalstructure of Ostrinia furnacalis Group IV chitinase [Ostrinia furnacalis],6JMB_A Chain A, ofchtiv-allosamidin [Ostrinia furnacalis]

Crystalstructure of Ostrinia furnacalis Group IV chitinase [Ostrinia furnacalis]

Uncharacterized glycosylase YvbX OS=Bacillus subtilis (strain 168) OX=224308 GN=yvbX PE=3 SV=1

Putative glycosylase YkvQ OS=Bacillus subtilis (strain 168) OX=224308 GN=ykvQ PE=3 SV=1

Putative sporulation-specific glycosylase YdhD OS=Bacillus subtilis (strain 168) OX=224308 GN=ydhD PE=1 SV=2

Cortical fragment-lytic enzyme OS=Bacillus subtilis (strain 168) OX=224308 GN=sleL PE=1 SV=2