>TIGR00329 gcp metalloendopeptidase, putative, glycoprotease family; InterPro: IPR000905 Metalloproteases are the most diverse of the four main types of protease, with more than 50 families identified to date. In these enzymes, a divalent cation, usually zinc, activates the water molecule. The metal ion is held in place by amino acid ligands, usually three in number. The known metal ligands are His, Glu, Asp or Lys and at least one other residue is required for catalysis, which may play an electrophillic role. Of the known metalloproteases, around half contain an HEXXH motif, which has been shown in crystallographic studies to form part of the metal-binding site . The HEXXH motif is relatively common, but can be more stringently defined for metalloproteases as 'abXHEbbHbc', where 'a' is most often valine or threonine and forms part of the S1' subsite in thermolysin and neprilysin, 'b' is an uncharged residue, and 'c' a hydrophobic residue. Proline is never found in this site, possibly because it would break the helical structure adopted by this motif in metalloproteases . Peptidases are grouped into clans and families. Clans are groups of families for which there is evidence of common ancestry. Each clan is identified with two letters, the first representing the catalytic type of the families included in the clan (with the letter 'P' being used for a clan containing families of more than one of the catalytic types serine, threonine and cysteine). Some families cannot yet be assigned to clans, and when a formal assignment is required, such a family is described as belonging to clan A-, C-, M-, S-, T- or U-, according to the catalytic type. Some clans are divided into subclans because there is evidence of a very ancient divergence within the clan, for example MA(E), the gluzincins, and MA(M), the metzincins. Families are grouped by their catalytic type, the first character representing the catalytic type: A, aspartic; C, cysteine; G, glutamic acid; M, metallo; S, serine; T, threonine; and U, unknown. The serine, threonine and cysteine peptidases utilise the amino acid as a nucleophile and form an acyl intermediate - these peptidases can also readily act as transferases. In the case of aspartic, glutamic and metallopeptidases, the nucleophile is an activated water molecule. This group of metallopeptidases belong to MEROPS peptidase family M22 (clan MK). The type example being O-sialoglycoprotein endopeptidase from Pasteurella haemolytica (Mannheimia haemolytica). O-Sialoglycoprotein endopeptidase is secreted by the bacterium P. haemolytica, and digests only proteins that are heavily sialylated, in particular those with sialylated serine and threonine residues . Substrate proteins include glycophorin A and leukocyte surface antigens CD34, CD43, CD44 and CD45 , . Removal of glycosylation, by treatment with neuraminidase, completely negates susceptibility to O-sialoglycoprotein endopeptidase digestion , . Sequence similarity searches have revealed other members of the M22 family, from yeast, Mycobacterium, Haemophilus influenzae and the cyanobacterium Synechocystis . The zinc-binding and catalytic residues of this family have not been determined, although the motif HMEGH may be a zinc-binding region .; GO: 0008450 O-sialoglycoprotein endopeptidase activity, 0006508 proteolysis.

Probab=100.00 E-value=0 Score=793.02 Aligned_cols=311 Identities=45% Similarity=0.738 Sum_probs=292.6 Q ss_pred EEEECCCHHHEEEEEECCC--CCCEEEEEEEECCCCCCCCCCCCCCHHHHHHHHHHHHHHHHHHHHHCCCCCCCCCEEEE Q ss_conf 8750260220778873388--88418988731133462121871455999999996999999999983898224536874 Q gi|254781038|r 9 IGIETSCDETAVAVVRRKD--SHGEILAEAVLSQIDQHGHYGGVVPEVAARAHVDVLDILIKQTLLRANMQISDMDSIAV 86 (363) Q Consensus 9 LgIETScd~tsvaiv~~~~--~~~~il~~~~~sq~~~~~~~GGv~P~~A~~~H~~~l~~li~~~l~~a~~~~~~id~Iav 86 (363) T Consensus 1 LgIEtsCDdt~vaiv~~~~ksaa~~v~an~~~~~~~~H~~~GGvvPe~Asr~H~~~~~~L~~~Al~~~~~~~~~I~~IA~ 80 (337) T TIGR00329 1 LGIETSCDDTGVAIVDEEDKSAAGNVLANIKISQIKLHAKYGGVVPELASRHHAENIPPLLERALKESNVDISEIDLIAV 80 (337) T ss_pred CCCCCCHHHCEEEEEECCHHHHHHHHHHHCCCCHHHHHHCCCCCCCHHHHHHHHHHHHHHHHHHHHHHCCCCCCCCEEEE T ss_conf 98650142512423323303345556652135512410002893605899889998899999999982887010257898 Q ss_pred CCCCCHHHHHHHHHHHHHHHHHHHCCCCCCCHHHHHHHHCCCCCCC---CCCCCEEEEEECCCEEEEEECCCCCCEECCC Q ss_conf 0664301256779999999887514864333036776530132256---7998439997068747999837564300022 Q gi|254781038|r 87 TAGPGLMGGLIVGLMTAKAISYVSHKPFYAINHLEGHILTARLTDD---IAFPYLVLLVSGGHTQILLVRDVAHYDRLGT 163 (363) Q Consensus 87 t~gPG~~~~L~vG~~~Ak~la~~~~~Pli~VnH~~aH~~~~~l~~~---~~~PfL~LlvSGGhT~l~~~~~~~~~~ilg~ 163 (363) T Consensus 81 t~~PGL~g~L~vGat~Ar~La~~l~kPligv~H~~GH~~~~~l~~~~~~~~~P~~~LlVSGGHT~~~~~~~~~~~e~~ge 160 (337) T TIGR00329 81 TSGPGLGGALIVGATFARSLALSLDKPLIGVNHLLGHIYAPLLDTNLNQLQFPFVSLLVSGGHTQIIAVKGIGDYEILGE 160 (337) T ss_pred ECCCCCCCHHHHHHHHHHHHHHHHCCCCCCHHHHHHHHHHHHHCCCCCCCCCCCEEEEEECCEEEEEEEECCCCEEEEEE T ss_conf 55879851468999999999898728955145789999887414777453667316777540115322304675789852 Q ss_pred CCCCCHHHHHHHHHHHCCCC-----CCHHHHH-HHHHHHCCCCCCCCCCHHCCCCC----CCCCCCHHHHHHHHHHHHHC Q ss_conf 33630023888898852887-----6103556-66554057333458611106887----54221024589999998511 Q gi|254781038|r 164 TIDDALGECFDKIAKSLGLP-----YPGGVEI-EKAALMGDGKRFKFPCPLVQGTL----CDFSFSGLKTSVQKTICAFD 233 (363) Q Consensus 164 T~Dda~Ge~~DK~ar~Lgl~-----yPgGp~i-e~~A~~g~~~~~~~P~p~~~~~~----~dFSFSGLkTav~~~i~~~~ 233 (363) T Consensus 161 T~DdA~Ge~fDK~ar~~gl~Gt~iayPGGp~i~~~l~~~g~~~~f~~p~P~~~~~~~~~~lDfSFSGLkTa~~~~~~~~~ 240 (337) T TIGR00329 161 TLDDAVGEAFDKVARLLGLGGTMIAYPGGPAIEEELAKKGDEKTFYFPLPLTKKPMKRNMLDFSFSGLKTAALRKLEKLK 240 (337) T ss_pred EHHHHHHHHHHHHHHHHCCCCCEEECCCCCHHHHHHHCCCCCCCEECCCCCCCCCCCCCCCHHHHHHHHHHHHHHHHHHH T ss_conf 02245424467777761889626506897426899854788775542666213688763403337899999999998743 Q ss_pred -------CCCCCCHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHCCCCCCEEEEEHHHHHHHHHHHHHHHHHHHCC----C Q ss_conf -------20121068899999999999999999999999876214455236541334587999999999998689----8 Q gi|254781038|r 234 -------VLEKQDIADICASFQVTVVRILQARLKQGFLLFRKAFPHKQAVLVVSGGVASNHFIRASLIDLCVLHG----F 302 (363) Q Consensus 234 -------~~~~~~~~diaasfQ~~i~~~L~~k~~~a~~~~~~~~~~~~~~lvv~GGVaaN~~LR~~l~~~~~~~~----~ 302 (363) T Consensus 241 ~rkt~~~~~~~~~~~diA~~fQ~~~~~~Li~~~kral~~qPek-f~~~~~~~~~GGVsaN~~LR~~l~~~~~~~~stsf~ 319 (337) T TIGR00329 241 ERKTESSNLNEATKEDIAYSFQETAFDHLIEKTKRALKDQPEK-FTGPKELVLVGGVSANKRLREKLETLCQELNSTSFV 319 (337) T ss_pred HHHHCCCCCCCHHHHHHHHHHHHHHHHHHHHHHHHHHHHCHHH-HCCCCEEEEECCHHHHHHHHHHHHHHHHHCCCCEEE T ss_conf 3321035775101899999999999998899999998515054-317766999431888889999999999741783067 Q ss_pred EEEECCHHHCCCHHHHHH Q ss_conf 899628788772589999 Q gi|254781038|r 303 RFVAPPARLCTDNAVMIA 320 (363) Q Consensus 303 ~~~~P~~~~ctDNAaMIA 320 (363) T Consensus 320 ~~~~pp~~fC~DNgAMIa 337 (337) T TIGR00329 320 EFYYPPLEFCSDNGAMIA 337 (337) T ss_pred EEECCCCCCCCCCHHHCC T ss_conf 751278333576122149

HHsearch alignment for GI: 254781038 and conserved domain: TIGR00329