Isochorismate synthase MbtI; Involved in the incorporation of salicylate into the virulence-conferring salicylate-based siderophore mycobactin. Catalyzes the initial conversion of chorismate to yield the intermediate isochorismate (isochorismate synthase activity), and the subsequent elimination of the enolpyruvyl side chain to give salicylate (isochorismate pyruvate-lyase activity). In the absence of magnesium, MbtI displays a chorismate mutase activity and converts chorismate to prephenate.

Phenyloxazoline synthase MbtB (phenyloxazoline synthetase); Involved in the initial steps of the mycobactin biosynthetic pathway. Putatively couples activated salicylic acid with serine or threonine and cyclizes this precursor to the hydroxyphenyloxazoline ring system present in this class of siderophores. Essential for growth in macrophages; Belongs to the ATP-dependent AMP-binding enzyme family. MbtB subfamily.

Putative conserved protein MbtH; Could be involved in mycobactin synthesis.

Rv2380c, (MTCY22H8.05), len: 1682 aa. MbtE, peptide synthetase (see citations below), similar in part to several synthases e.g. O07944|SNBDE pristinamycin I synthase 3 and 4 from Streptomyces pristinaespiralis (4848 aa), FASTA scores: opt: 2635, E(): 1.9e-146, (36.8% identity in 1657 aa overlap); O05647|SNBDE virginiamycin S synthetase (fragment) from Streptomyces virginiae (1997 aa) FASTA scores: opt: 2580, E(): 1.6e-143, (40.65% identity in 1163 aa overlap); Q9R9I2|DHBF protein involved in siderophore production from Bacillus subtilis (2378 aa),FASTA scores: opt: 2388, E(): 3.6e-132, [...]

Polyketide synthetase MbtD (polyketide synthase); Rv2381c, (MTCY22H8.04), len: 1004 aa. MbtD,polyketide synthase (see citations below), similar in part to several synthases e.g. Q03132|ERY2_SACER|ERYA erythronolide synthase, modules 3 and 4 from Saccharopolyspora erythraea (Streptomyces erythraeus) (3567 aa), FASTA scores: opt: 971, E(): 1e-46, (29.35% identity in 1043 aa overlap); Q9F829|megaii megalomicin 6-deoxyerythronolide B synthase 2 from Micromonospora megalomicea subsp. nigra (3562 aa), FASTA scores: opt: 787,E(): 2.4e-36, (29.35% identity in 1032 aa overlap); Q9L4W4|NYSB poly [...]

Polyketide synthetase MbtC (polyketide synthase); Rv2382c, (MTCY22H8.03), len: 444 aa. MbtC,polyketide synthase (see citations below), similar in part to several synthases e.g. Q9F7T9 avermectin polyketide synthase (fragment) from Streptomyces avermitilis (3626 aa), FASTA scores: opt: 1458, E(): 7e-82, (50.65% identity in 446 aa overlap); AAG23264|SPNA polyketide synthase loading and extender module 1 from Saccharopolyspora spinosa (2595 aa) FASTA scores: opt: 1441, E(): 6e-81,(49.1% identity in 446 aa overlap); O33954|TYLG tylactone synthase starter module and modules 1 & 2 from Strep [...]

Lysine-N-oxygenase MbtG (L-lysine 6-monooxygenase) (lysine N6-hydroxylase); Flavoprotein monooxygenase required for N-hydroxylation of the two acylated lysine residues during mycobactin assembly, thus producing the hydroxamate groups necessary for iron sequestration. Is also able, but less efficiently, to hydroxylate L-lysine (non acylated) in vitro.

Rv3402c, (MTCY78.26), len: 412 aa. Conserved hypothetical protein, probably involved in cell process,similar to various proteins generally involved in extracellular compounds (lipopolysaccharide O-antigen) biosynthesis e.g. O68392|RFBE perosamine synthetase from Brucella melitensis (367 aa), FASTA scores: opt: 420, E(): 1.2e-19, (26.15% identity in 375 aa overlap); Q9L6C1 3,4-dehydratase-like protein from Streptomyces antibioticus (393 aa), FASTA scores: opt: 419, E(): 1.5e-19, (30.65% identity in 385 aa overlap); Q9RR26|OLENI dehydratase from Streptomyces antibioticus (393 aa), FASTA [...]

Probable lipase LipH; Esterase that can hydrolyze short-chain esters with the carbon chain containing 2 to 12 carbon atoms. In vitro, pNP-butyrate is the preferred substrate.