S-Acetyltransferase

Spatially, the enzyme activities are arranged into three different domains. Domain 1 catalyzes the entry of the substrates acetyl CoA and malonyl CoA by [ACPj-S-acetyltransferase [1] and [ACPJ-Smalonyl transferase [2] and subsequent condensation of the two partners by 3-oxoacyl-[ACP] synthase [3]. Domain 2 catalyzes the conversion of the 3-0X0 group to a CH2 group by 3-oxoacyl-[ACP]-reductase [4], 3-hydroxyacyl-[ACP -dehydratase [5], and enoyl-[ACP]-re-... 

PereZ Gonzalez JA, Ruiz D, Esteban JA. Jimenez A. Cloning and characterization of the gene encoding a blasticidin S acetyltransferase from Streptoverticillum sp. Gene 1990 86 129-134. 

The metabolism of foreign compounds (xenobiotics) often takes place in two consecutive reactions, classically referred to as phases one and two. Phase I is a functionalization of the lipophilic compound that can be used to attach a conjugate in Phase II. The conjugated product is usually sufficiently water-soluble to be excretable into the urine. The most important biotransformations of Phase I are aromatic and aliphatic hydroxylations catalyzed by cytochromes P450. Other Phase I enzymes are for example epoxide hydrolases or carboxylesterases. Typical Phase II enzymes are UDP-glucuronosyltrans-ferases, sulfotransferases, N-acetyltransferases and methyltransferases e.g. thiopurin S-methyltransferase. 

Manufacturing processes for cephalosporin C and benzylpenicilhn are broadly similar. In common with mai other antibiotic fermentations, no specific precursor feed is necessary for cephalosporin C. There is sufficient acetyl group substrate for the terminal acetyltransferase reaction available fiom the organism s metabolic pool. 

Chen, G., Wang, L., Liu, S., Chuang, C. and Roche, T.E. (1996) Activated function of the pyruvate dehydrogenase phosphatase through Ca2+-facilitated binding to the inner lipoyl domain of the dihydrolipoyl acetyltransferase. Journal of Biological Chemistry 271,28064-28070. 

RM. Iuvone, G. Tosini, N. Pozdeyev, R. Haque, D.C. Klein, and S.S. Chaurasia, Circadian clocks, clock networks, arylalkylarnine N-acetyltransferase, and melatonin in the retina. Prog. Retinal Eye Res. 24, 433-456 (2005). 

ACh was first proposed as a mediator of cellular function by Hunt in 1907, and in 1914 Dale [2] pointed out that its action closely mimicked the response of parasympathetic nerve stimulation (see Ch. 10). Loewi, in 1921, provided clear evidence for ACh release by nerve stimulation. Separate receptors that explained the variety of actions of ACh became apparent in Dale s early experiments [2]. The nicotinic ACh receptor was the first transmitter receptor to be purified and to have its primary structure determined [3, 4]. The primary structures of most subtypes of both nicotinic and muscarinic receptors, the cholinesterases (ChE), choline acetyltransferase (ChAT), the choline and ACh transporters have been ascertained. Three-dimensional structures for several of these proteins or surrogates within the same protein family are also known. 

The translation of the sequence of the cDNA encoding deacetylvindoline 4-O-acetyltransferase compared to other putative plant acetyltransferases revealed a conserved region near the carboxy terminus of the proteins. This sequence was used to design a degenerate antisense oligodeoxynucleotide primer for PCR. The sense primer was based upon an internal peptide sequence of salutaridinol 7-0-acetyltransferase. This approach finally yielded a partial cDNA that encoded salutaridinol 7-O-acetyltransferase. The full-length clone was obtained by RACE-PCR and was functionally expressed in S. frugiperda Sf9 cells.28 The amino acid sequence of salutaridinol 7-O-acetyltransferase is most similar (37% identity) to that of deacetylvindoline acetyltransferase of C. roseus.27... 

Fig. 10.8 Selected cDNAs isolated in recent years that encode enzymes involved in the biosynthesis of various classes of isoquinoline alkaloids. 6-OMT, norcoclaurine 6-0-methyltransferase 23 CYP80A1, berbamunine synthase 19 CYP80B1, (S)-A-methylcoclaurine 3 -hydroxylase 20 CPR, cytochrome P-450 reductase 29 4 -OMT, (5)-3 -hydroxy-A-methylcoclaurine 4 -0-methyltransferase 30 BBE, berberine bridge enzyme 12 SalAT, salutaridinol 7-O-acetyltransferase 28 COR, codeinone reductase.25...

Lo Leggio, L., Dal Degan, F., Poulsen, P., Andersen, S. M., and Larsen, S. (2003). The structure and specificity of Escherichia coli maltose acetyltransferase give new insight into the LacA family of acyltransferases. Biochemistry 42, 5225-5235. 

Phosphine complexes, osmium, 19 642 Phosphine coordination complexes, of uranium, 25 436 Phosphine derivatives, 19 28 Phosphine oxide(s), 11 495-496 19 66 predicted deviations from Raoult s law based on hydrogen-bonding interactions, 8 814t in salicylic acid manufacture, 22 8 Phosphine oxide diols/triols, 11 501 Phosphine selenides, 22 90 Phosphinic acid, 19 20, 54-55 Phosphinic anhydride, 11 499 Phosphinothricin acetyltransferase (PAT) proteins, 13 360 Phosphite esters, 19 20 Phosphites, in VDC polymer stabilization, 25 720... 

Qin S, Parthun MR (2006) Recruitment of the type B histone acetyltransferase Hatlp to chromatin is linked to DNA double-strand breaks. Mol.Cell.Biol 26 3649-3658... 

Bordoli L, Husser S, Luthi U, Netsch M, Osmani H, Eckner R (2001a) Functional analysis of the p300 acetyltransferase domain the PHD finger of p300 but not of CBP is dispensable for enzymatic activity. Nucleic Acids Res 29 4462 471... 

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