EC                Enzyme                                 

meromycolic acid 3-oxoacyl-(acyl carrier protein) synthase II;
kasB (gene name);
beta-ketoacyl-acyl carrier protein synthase KasB
Transferring groups other than aminoacyl groups
ultra-long-chain di-unsaturated fattyl acyl-[acyl-carrier protein]:malonyl-[acyl-carrier protein] C-acyltransferase (decarboxylating)
an ultra-long-chain di-unsaturated acyl-[acyl-carrier protein] + a malonyl-[acyl-carrier protein] = an ultra-long-chain di-unsaturated 3-oxo-fatty acyl-[acyl-carrier protein] + CO2 + a holo-[acyl-carrier protein]
ultra-long-chain di-unsaturated acyl-[acyl-carrier protein];
malonyl-[acyl-carrier protein] [CPD:C01209]
ultra-long-chain di-unsaturated 3-oxo-fatty acyl-[acyl-carrier protein];
CO2 [CPD:C00011];
holo-[acyl-carrier protein] [CPD:C00229]
The enzyme is part of the fatty acid synthase (FAS) II system of mycobacteria, which extends modified products of the FAS I system, eventually forming meromycolic acids that are incorporated into mycolic acids. Meromycolic acids consist of a long chain, typically 50-60 carbons, which is functionalized by different groups.Two 3-oxoacyl-(acyl carrier protein) synthases function within the FAS II system, encoded by the kasA and kasB genes. The two enzymes share some sequence identity but function independently on separate sets of substrates. KasB differs from KasA (EC, meromycolic acid 3-oxoacyl-(acyl carrier protein) synthase I), by preferring longer substrates (closer to the upper limit), which also contain two double bonds.
EC created 2019
K11609  beta-ketoacyl ACP synthase
MTU: Rv2245(kasA) Rv2246(kasB)
MTV: RVBD_2245 RVBD_2246
MTC: MT2305(fabF-1) MT2306(fabF-2)
MRA: MRA_2265(kasA) MRA_2266(kasB)
MTF: TBFG_12274 TBFG_12275
MTB: TBMG_01734 TBMG_01735
MTK: TBSG_01744 TBSG_01745
MTZ: TBXG_001716 TBXG_001717
MTG: MRGA327_13860
MTI: MRGA423_13980 MRGA423_13985
MTUR: CFBS_2378 CFBS_2379(kasB)
MTO: MTCTRI2_2281(kasA) MTCTRI2_2282(kasB)
MTD: UDA_2245(kasA) UDA_2246(kasB)
MTN: ERDMAN_2470(kasA) ERDMAN_2471(kasB)
MTUH: I917_15810
MTUT: HKBT1_2369 HKBT1_2370(kasB)
MTUU: HKBT2_2371 HKBT2_2372(kasB)
MBO: BQ2027_MB2269(kasA) BQ2027_MB2270(kasB)
MBB: BCG_2262(kasA) BCG_2263(kasB)
MBT: JTY_2256(kasA) JTY_2257(kasB)
MBM: BCGMEX_2250(kasA) BCGMEX_2251(kasB)
MAF: MAF_22560(kasA) MAF_22570(kasB)
MCE: MCAN_22671(kasA) MCAN_22681(kasB)
MCQ: BN44_50188(kasA) BN44_50189(kasB)
MCV: BN43_31488(kasA) BN43_31489(kasB)
MCX: BN42_40169(kasA) BN42_40170(kasB)
MCZ: BN45_50577(kasA) BN45_50578(kasB)
MLE: ML1655(kasA) ML1656(kasB)
MLB: MLBr01655(kasA) MLBr01656(kasB)
MPA: MAP_1998(kasA) MAP_1999(kasB) MAP_3485(kasB)
MMAN: MMAN_18020(kasA) MMAN_18030(kasB_1) MMAN_30190(kasB_2)
MUL: MUL_1303(kasB) MUL_1304(kasA)
MMI: MMAR_3338(kasA) MMAR_3339(kasB)
MMAE: MMARE11_32390(kasA) MMARE11_32400(kasB)
MLI: MULP_03599(kasA) MULP_03600(kasB)
MSHG: MSG_01053(kasB_1) MSG_03170(kasA) MSG_03171(kasB_2)
MFJ: MFLOJ_00450(kasB_1) MFLOJ_00460(kasA) MFLOJ_23320(kasB_2)
MSTO: MSTO_01110(kasB_1) MSTO_01120(kasA) MSTO_27280(kasB_2)
MSIM: MSIM_14500(kasB_1) MSIM_45150(kasB_2) MSIM_45160(kasA)
MSAK: MSAS_12200(kasA) MSAS_12210(kasB_1) MSAS_12510(kasB_2)
MXE: MYXE_20720(kasB) MYXE_20730(kasA) MYXE_43070
MNV: MNVI_22730 MNVI_45150(kasA) MNVI_45160(kasB)
MNM: MNVM_02370(kasA) MNVM_02380(kasB) MNVM_40280
MCOO: MCOO_12820 MCOO_12830(kasB_1) MCOO_39080(kasB_2)
MBAI: MB901379_03010(kasA_1) MB901379_03011(kasB)
MSEO: MSEO_14160(kasB_1) MSEO_19570(kasA) MSEO_19580(kasB_2)
MPSE: MPSD_34150(kasA) MPSD_34160(kasB)
MSHO: MSHO_47500(kasA) MSHO_47510(kasB)
MLJ: MLAC_22590(kasA) MLAC_22600(kasB)
MBRD: MBRA_10910 MBRA_35610(kasB) MBRA_35620(kasA)
MSHJ: MSHI_10160(kasB) MSHI_10170(kasA)
MKR: MKOR_04700(kasB) MKOR_04710(kasA)
MSG: MSMEI_1170(kasB) MSMEI_4227(kasA) MSMEI_4228(kasB)
MPHL: MPHLCCUG_01036(kasB_1) MPHLCCUG_03392(kasA) MPHLCCUG_03393(kasB_2)
MTHN: 4412656_01785(kasB) 4412656_01786(kasA_1)
MHAS: MHAS_00020(kasB_1) MHAS_01448(kasB_2) MHAS_01449(kasA)
MAUU: NCTC10437_03513(kasA) NCTC10437_03514(kasB_1) NCTC10437_04668(kasB_2)
MSAL: DSM43276_01633(kasA_1) DSM43276_04441(kasA_2)
MJD: JDM601_1649(kasB) JDM601_1650(kasA) JDM601_2027(kasB)
MTER: 4434518_01562(kasB_1) 4434518_01563(kasA) 4434518_01976(kasB_2)
MMIN: MMIN_32490(kasB) MMIN_32500(kasA)
MHIB: MHIB_10830(kasB) MHIB_10840(kasA) MHIB_26020
ASD: AS9A_1223(fabF)
NFA: NFA_16170(kasA)
NFR: ERS450000_02543(kasA_1)
NCY: NOCYR_1672(fabF) NOCYR_5164(kasA)
NNO: NONO_c06540(kasA1) NONO_c13390(kasA2) NONO_c20820(kasA3) NONO_c39590(kasA4) NONO_c40520(kasA5)
NAD: NCTC11293_00291(kasA_1) NCTC11293_02031(kasA_2) NCTC11293_02578(kasA_4)
RHA: RHA1_ro01201(fabF)
RER: RER_36740(fabF)
REY: O5Y_16895
ROP: ROP_09240(fabF) ROP_12330(fabF)
REQ: REQ_28970(kasA)
RHB: NY08_584
RFA: A3L23_03833(kasA)
RHS: A3Q41_04409(kasA)
RHU: A3Q40_01110(kasA)
RRT: 4535765_03064(fabF_2)
RCR: NCTC10994_04197(fabF_3)
GBR: Gbro_3123
GPO: GPOL_c28870(kasA)
GOR: KTR9_3116
GRU: GCWB2_16225(kasA)
GOM: D7316_00150(kasA)
 » show all
1  [PMID:11600501]
Schaeffer ML, Agnihotri G, Volker C, Kallender H, Brennan PJ, Lonsdale JT
Purification and biochemical characterization of the Mycobacterium tuberculosis beta-ketoacyl-acyl carrier protein synthases KasA and KasB.
J Biol Chem 276:47029-37 (2001)
2  [PMID:12950920]
Gao LY, Laval F, Lawson EH, Groger RK, Woodruff A, Morisaki JH, Cox JS, Daffe M, Brown EJ
Requirement for kasB in Mycobacterium mycolic acid biosynthesis, cell wall impermeability and intracellular survival: implications for therapy.
Mol Microbiol 49:1547-63 (2003)
3  [PMID:16873379]
Molle V, Brown AK, Besra GS, Cozzone AJ, Kremer L
The condensing activities of the Mycobacterium tuberculosis type II fatty acid synthase are differentially regulated by phosphorylation.
J Biol Chem 281:30094-103 (2006)
4  [PMID:17360388]
Bhatt A, Fujiwara N, Bhatt K, Gurcha SS, Kremer L, Chen B, Chan J, Porcelli SA, Kobayashi K, Besra GS, Jacobs WR Jr
Deletion of kasB in Mycobacterium tuberculosis causes loss of acid-fastness and subclinical latent tuberculosis in immunocompetent mice.
Proc Natl Acad Sci U S A 104:5157-62 (2007)
5  [PMID:22516756]
Yamada H, Bhatt A, Danev R, Fujiwara N, Maeda S, Mitarai S, Chikamatsu K, Aono A, Nitta K, Jacobs WR Jr, Nagayama K
Non-acid-fastness in Mycobacterium tuberculosis DeltakasB mutant correlates with  the cell envelope electron density.
Tuberculosis (Edinb) 92:351-7 (2012)
6  [PMID:24809459]
Vilcheze C, Molle V, Carrere-Kremer S, Leiba J, Mourey L, Shenai S, Baronian G, Tufariello J, Hartman T, Veyron-Churlet R, Trivelli X, Tiwari S, Weinrick B, Alland D, Guerardel Y, Jacobs WR Jr, Kremer L
Phosphorylation of KasB regulates virulence and acid-fastness in Mycobacterium tuberculosis.
PLoS Pathog 10:e1004115 (2014)
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