:Alpha-lytic endopeptidase

{{Infobox enzyme

| Name = Alpha-lytic endopeptidase

| EC_number = 3.4.21.12

| CAS_number = 37288-76-9

| GO_code =

| image =

| width =

| caption =

}}

Alpha-lytic endopeptidase or Alpha-lytic protease ({{EC number|3.4.21.12}}, myxobacter alpha-lytic proteinase, alpha-lytic proteinase, alpha-lytic protease, Mycobacterium sorangium alpha-lytic proteinase, Myxobacter 495 alpha-lytic proteinase) is an enzyme isolated from the myxobacterium Lysobacter enzymogenes.{{cite journal | vauthors = Olson MO, Nagabhushan N, Dzwiniel M, Smillie LB, Whitaker DR | title = Primary structure of alpha-lytic protease: a bacterial homologue of the pancreatic serine proteases | journal = Nature | volume = 228 | issue = 5270 | pages = 438–42 | date = October 1970 | pmid = 5482494 | doi = 10.1038/228438a0 | bibcode = 1970Natur.228..438O }}{{cite book | chapter = Structure and function of serine proteases | title = New Comprehensive Biochemistry: Hydrolytic Enzymes | vauthors = Polgar L |year = 1987 |volume = 16 |pages = 159–200 | veditors = Neuberger A, Brocklehurst K |publisher = Elsevier |location = Amsterdam |chapter-url = https://www.elsevier.com/books/hydrolytic-enzymes/brocklehurst/978-0-444-80886-8}}{{cite journal | vauthors = Epstein DM, Wensink PC | title = The alpha-lytic protease gene of Lysobacter enzymogenes. The nucleotide sequence predicts a large prepro-peptide with homology to pro-peptides of other chymotrypsin-like enzymes | journal = The Journal of Biological Chemistry | volume = 263 | issue = 32 | pages = 16586–90 | date = November 1988 | doi = 10.1016/S0021-9258(18)37430-1 | doi-access = free | pmid = 3053694 }}{{cite journal | vauthors = Bone R, Frank D, Kettner CA, Agard DA | title = Structural analysis of specificity: alpha-lytic protease complexes with analogues of reaction intermediates | journal = Biochemistry | volume = 28 | issue = 19 | pages = 7600–9 | date = September 1989 | pmid = 2611204 | doi = 10.1021/bi00445a015 }} This enzyme is a serine protease that catalyses the breakage of peptide bonds using a hydrolysis chemical reaction. Alpha-lytic protease was named based on the observed cleavage specificity for the α position of the tetrapeptide component in gram-positive bacterial cell walls (alanine). Alpha-lytic protease is also capable of digesting elastin and other proteins.

This protease was recently applied to proteome digestion for production of peptides for mass spectrometry-based proteomics,{{cite journal | vauthors = Meyer JG, Kim S, Maltby DA, Ghassemian M, Bandeira N, Komives EA | title = Expanding proteome coverage with orthogonal-specificity α-lytic proteases | journal = Molecular & Cellular Proteomics | volume = 13 | issue = 3 | pages = 823–35 | date = March 2014 | pmid = 24425750 | pmc = 3945911 | doi = 10.1074/mcp.M113.034710 | doi-access = free }} where it was found to cleave preferentially after several small amino acids, including alanine, serine, threonine, valine, and to a lesser extent, methionine. This specificity is very different than the most commonly-used protease for proteomics, trypsin, which cleaves only after arginine and lysine.

Alpha-lytic protease was also recently reported to find utility as part of a method to map endogenous SUMO modification sites in the proteome.{{cite journal | vauthors = Lumpkin RJ, Gu H, Zhu Y, Leonard M, Ahmad AS, Clauser KR, Meyer JG, Bennett EJ, Komives EA | title = Site-specific identification and quantitation of endogenous SUMO modifications under native conditions | language = En | journal = Nature Communications | volume = 8 | issue = 1 | pages = 1171 | date = October 2017 | pmid = 29079793 | doi = 10.1038/s41467-017-01271-3 | pmc = 5660086 | bibcode = 2017NatCo...8.1171L }}