Fatty acid synthetase catalyzes the formation of long-chain fatty acids from acetyl-CoA, malonyl-CoA and NADPH. The beta subunit contains domains for: [acyl-carrier-protein] acetyltransferase and malonyltransferase, S-acyl fatty acid synthase thioesterase, enoyl-[acyl-carrier-protein] reductase, and 3-hydroxypalmitoyl-[acyl-carrier-protein] dehydratase. acetyl-CoA + 2n H(+) + n malonyl-CoA + 2n NADPH = a long-chain fatty acyl-CoA + n CO2 + n CoA + H2O + 2n NADP(+) acetyl-CoA + holo-[ACP] = acetyl-[ACP] + CoA holo-[ACP] + malonyl-CoA = CoA + malonyl-[ACP] a (3R)-hydroxyacyl-[ACP] = a (2E)-enoyl-[ACP] + H2O a 2,3-saturated acyl-[ACP] + NAD(+) = a (2E)-enoyl-[ACP] + H(+) + NADH (9Z)-octadecenoyl-[ACP] + H2O = (9Z)-octadecenoate + H(+) + holo-[ACP] [Alpha(6)beta(6)] hexamers of two multifunctional subunits (alpha and beta). Present with 91800 molecules/cell in log phase SD medium. Belongs to the fungal fatty acid synthetase subunit beta family.