Peptidase family M23. Members of this family are zinc metallopeptidases with a range of specificities. The peptidase family M23 is included in this family, these are Gly-Gly endopeptidases. Peptidase family M23 are also endopeptidases. This family also includes some bacterial lipoproteins for which no proteolytic activity has been demonstrated. This family also includes leukocyte cell-derived chemotaxin 2 (LECT2) proteins. LECT2 is a liver-specific protein which is thought to be linked to hepatocyte growth although the exact function of this protein is unknown.

Murein DD-endopeptidase MepM and murein hydrolase activator NlpD, contain LysM domain [Cell wall/membrane/envelope biogenesis].

M23 family metallopeptidase, also known as beta-lytic metallopeptidase, and similar proteins. This model describes the metallopeptidase M23 family, which includes beta-lytic metallopeptidase and lysostaphin. Members of this family are zinc endopeptidases that lyse bacterial cell wall peptidoglycans; they cleave either the N-acylmuramoyl-Ala bond between the cell wall peptidoglycan and the cross-linking peptide (e.g. beta-lytic endopeptidase) or a bond within the cross-linking peptide (e.g. stapholysin, and lysostaphin). Beta-lytic metallopeptidase, formerly known as beta-lytic protease, has a preference for cleavage of Gly-X bonds and favors hydrophobic or apolar residues on either side. It inhibits growth of sensitive organisms and may potentially serve as an antimicrobial agent. Lysostaphin, produced by Staphylococcus genus, cleaves pentaglycine cross-bridges of cell wall peptidoglycan, acting as autolysins to maintain cell wall metabolism or as toxins and weapons against competing strains. Staphylolysin (also known as LasA) is implicated in a range of processes related to Pseudomonas virulence, including stimulating shedding of the ectodomain of cell surface heparan sulphate proteoglycan syndecan-1, and elastin degradation in connective tissue. Its active site is less constricted and contains a five-coordinate zinc ion with trigonal bipyramidal geometry and two metal-bound water molecules, possibly contributing to its activity against a wider range of substrates than those used by related lytic enzymes, consistent with its multiple roles in Pseudomonas virulence. The family includes members that do not appear to have the conserved zinc-binding site and might be lipoproteins lacking proteolytic activity.

G5 domain. This domain is found in a wide range of extracellular proteins. It is found tandemly repeated in up to 8 copies. It is found in the N-terminus of peptidases belonging to the M26 family which cleave human IgA. The domain is also found in proteins involved in metabolism of bacterial cell walls suggesting this domain may have an adhesive function.

Septal ring factor EnvC, activator of murein hydrolases AmiA and AmiB [Cell cycle control, cell division, chromosome partitioning].

Crystalstructure of Csd1-Csd2 dimer I [Helicobacter pylori 26695],5J1L_C Crystal structure of Csd1-Csd2 dimer I [Helicobacter pylori 26695],5J1M_A Crystal structure of Csd1-Csd2 dimer II [Helicobacter pylori 26695],5J1M_C Crystal structure of Csd1-Csd2 dimer II [Helicobacter pylori 26695]

ChainA, Peptidase M23 [Campylobacter jejuni],6JMY_A Chain A, Peptidase M23 [Campylobacter jejuni],6KV1_A Chain A, Peptidase M23 [Campylobacter jejuni]

Crystalstructure of NMB0315 [Neisseria meningitidis ATCC 13091],3SLU_B Crystal structure of NMB0315 [Neisseria meningitidis ATCC 13091]

1.93Angstrom Resolution Crystal Structure of Peptidase M23 from Neisseria gonorrhoeae. [Neisseria gonorrhoeae FA 1090]

ShyAEndopeptidase from Vibrio cholerae (Closed form) [Vibrio cholerae O1 biovar El Tor str. N16961],6UE4_B ShyA Endopeptidase from Vibrio cholerae (Closed form) [Vibrio cholerae O1 biovar El Tor str. N16961]

Murein hydrolase activator NlpD OS=Salmonella typhi OX=90370 GN=nlpD PE=3 SV=2

Murein hydrolase activator NlpD OS=Salmonella typhimurium (strain LT2 / SGSC1412 / ATCC 700720) OX=99287 GN=nlpD PE=3 SV=2

Murein hydrolase activator NlpD OS=Salmonella dublin OX=98360 GN=nlpD PE=2 SV=2

Lipoprotein NlpD/LppB homolog OS=Pseudomonas aeruginosa (strain ATCC 15692 / DSM 22644 / CIP 104116 / JCM 14847 / LMG 12228 / 1C / PRS 101 / PAO1) OX=208964 GN=PA3623 PE=3 SV=1

Murein DD-endopeptidase MepM OS=Shigella flexneri OX=623 GN=mepM PE=3 SV=1