Additional remarks phenotype | Mutant/mutation
The mutant lacks expression of FABZ.
Protein (function)
FABZ is an enzyme of the bacterial like type II fatty acid biosynthesis (FAS-II) pathway. In Plasmodium FAS-II enzymes have been localized to the apicoplast, a nonphotosynthetic plastid organelle of cyanobacterial origin.
FAS-II requires acetyl-Coenzyme A (CoA), which can be converted from pyruvate by the pyruvate dehydrogenase complex. Acetyl-CoA carboxylase converts acetyl-CoA to malonyl-CoA, which is tethered to an acyl carrier protein (ACP) by malonyl-CoA:ACP transacylase (FabD). This produces malonyl-ACP, which, in conjunction with acetyl-CoA, is acted upon by β-ketoacyl-ACP synthase III (Fab H) to form β-ketoacyl-ACP. This precursor enters the FAS-II elongation cycle, mediated by FabB/F (β-ketoacyl-acyl-carrier-protein (ACP) synthase), FabG (β-ketoacyl-ACP reductase), FabZ/A (β-hydroxyacyl-ACP dehydratase), and FabI (trans-2-enoyl-ACP reductase). These four FAS-II enzymes iteratively catalyze the addition of two carbon chains to a growing fatty acyl carbon chain via condensation, reduction, dehydration, and reduction steps, respectively.
Phenotype
The phenotype analyses show that FABZ is not essential for blood stage development, mosquito stage development. The results indicate an a role during liver stage development. See also mutants RMgm-183 and RMgm-197 for a more detailed analysis of the phenotype during liver stage development of mutants lacking expression of other enzymes (FABB/F, FABI) of the FASII pathway. These analyses indicate an essential role of these enzymes in the formation of infective liver stage merozoites demonstrating the importance of FASII pathway for synthesis of fatty acids during late liver stage development.
Additional information
Other mutants
RMgm-180: A mutant expressing myc tagged FABI
RMgm-181: A mutant expressing myc tagged FABZ
RMgm-182: A mutant expressing myc tagged FABG
RMgm-183: A mutant lacking expression of FABB/F
RMgm-197: A mutant lacking expression of FABI
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