Since the phospholipase B (PLB) was reported as a deacylase of both lecithin and lysolecithin yielding @entity1718 and @entity15001 (GPC), there was a question as to whether it is a single enzyme or a mixture of a phospholipase A2 (PLA2) and a lysophospholipase (LPL). We purified the PLB in @entity5449 and showed that it catalyzed deacylation of sn-1 and sn-2 @entity1718 of 1,2-diacylphospholipids and also sn-1 or sn-2 @entity1718 of 1- or 2-monoacylphospholipids (lysophospholipids). Further, it also has a monoacyllipase activity. The purified PLB is a glycoprotein with m.w. of 91,300. The sugar moiety is M9 only and the protein moiety consists of 603 @entity1522 . PLB, different from PLA2, shows other enzymatic activities, such as transacylase, lipase and acylesterase. PLB activity is influenced by various substances, e.g. detergents, @entity6743 , @entity4543 , @entity596 , and endogenous protease. Therefore, PLB might have broader roles than PLA2 in vivo. The database shows an extensive sequence similarity between @entity5449 PLB and fungal PLB, cPLA2 and patatin, suggesting a homologous relationship. The catalytic triad of cPLA2, Ser, @entity2574 and @entity534 , is also present in @entity5449 PLB. Other related PLBs, PLB/Lipases are discussed.

Reminiscence of phospholipase B in XXXX .

@entity1522 :: ('CHEBI:33709', 'Chemical') :: ['amino acids'] @entity596 :: ('CHEBI:29034', 'Chemical') :: ['Fe(3+)'] @entity15001 :: ('CHEBI:55397', 'Chemical') :: ['glycerophosphocholine'] @entity5449 :: ('5076', 'Species') :: ['Penicillium notatum', 'P. notatum'] @entity534 :: ('CHEBI:16467', 'Chemical') :: ['Arg'] @entity4543 :: ('MESH:D004986', 'Chemical') :: ['diethylether'] @entity1718 :: ('MESH:D005227', 'Chemical') :: ['fatty acids'] @entity2574 :: ('CHEBI:22660', 'Chemical') :: ['Asp'] @entity6743 :: ('MESH:D003840', 'Chemical') :: ['deoxycholate']
@entity5449 :: (5076,Species) :: ['Penicillium notatum']
