Dataset Information

Short-chain fatty acid activation by acyl-coenzyme A synthetases requires SIR2 protein function in Salmonella enterica and Saccharomyces cerevisiae.

ABSTRACT: SIR2 proteins have NAD(+)-dependent histone deacetylase activity, but no metabolic role has been assigned to any of these proteins. In Salmonella enterica, SIR2 function was required for activity of the acetyl-CoA synthetase (Acs) enzyme. A greater than two orders of magnitude increase in the specific activity of Acs enzyme synthesized by a sirtuin-deficient strain was measured after treatment with homogeneous S. enterica SIR2 protein. Human SIR2A and yeast SIR2 proteins restored growth of SIR2-deficient S. enterica on acetate and propionate, suggesting that eukaryotic cells may also use SIR2 proteins to control the synthesis of acetyl-CoA by the level of acetylation of acetyl-CoA synthetases. Consistent with this idea, growth of a quintuple sir2 hst1 hst2 hst3 hst4 mutant strain of the yeast Saccharomyces cerevisiae on acetate or propionate was severely impaired. The data suggest that the Hst3 and Hst4 proteins are the most important for allowing growth on these short-chain fatty acids.

SUBMITTER: Starai VJ

PROVIDER: S-EPMC1462443 | biostudies-other | 2003 Feb

REPOSITORIES: biostudies-other

ACCESS DATA

Publications

Short-chain fatty acid activation by acyl-coenzyme A synthetases requires SIR2 protein function in Salmonella enterica and Saccharomyces cerevisiae.

Starai Vincent J VJ Takahashi Hidekazu H Boeke Jef D JD Escalante-Semerena Jorge C JC

Genetics 20030201 2

SIR2 proteins have NAD(+)-dependent histone deacetylase activity, but no metabolic role has been assigned to any of these proteins. In Salmonella enterica, SIR2 function was required for activity of the acetyl-CoA synthetase (Acs) enzyme. A greater than two orders of magnitude increase in the specific activity of Acs enzyme synthesized by a sirtuin-deficient strain was measured after treatment with homogeneous S. enterica SIR2 protein. Human SIR2A and yeast SIR2 proteins restored growth of SIR2- ...[more]

PMID: 12618394

Similar Datasets

Project description:Bacterial steroid catabolism is an important component of the global carbon cycle and has applications in drug synthesis. Pathways for this catabolism involve multiple acyl coenzyme A (CoA) synthetases, which activate alkanoate substituents for ?-oxidation. The functions of these synthetases are poorly understood. We enzymatically characterized four distinct acyl-CoA synthetases from the cholate catabolic pathway of Rhodococcus jostii RHA1 and the cholesterol catabolic pathway of Mycobacterium tuberculosis. Phylogenetic analysis of 70 acyl-CoA synthetases predicted to be involved in steroid metabolism revealed that the characterized synthetases each represent an orthologous class with a distinct function in steroid side-chain degradation. The synthetases were specific for the length of alkanoate substituent. FadD19 from M. tuberculosis H37Rv (FadD19Mtb) transformed 3-oxo-4-cholesten-26-oate (kcat/Km = 0.33 × 10(5) ± 0.03 × 10(5) M(-1) s(-1)) and represents orthologs that activate the C8 side chain of cholesterol. Both CasGRHA1 and FadD17Mtb are steroid-24-oyl-CoA synthetases. CasG and its orthologs activate the C5 side chain of cholate, while FadD17 and its orthologs appear to activate the C5 side chain of one or more cholesterol metabolites. CasIRHA1 is a steroid-22-oyl-CoA synthetase, representing orthologs that activate metabolites with a C3 side chain, which accumulate during cholate catabolism. CasI had similar apparent specificities for substrates with intact or extensively degraded steroid nuclei, exemplified by 3-oxo-23,24-bisnorchol-4-en-22-oate and 1?(2'-propanoate)-3a?-H-4?(3?-propanoate)-7a?-methylhexahydro-5-indanone (kcat/Km = 2.4 × 10(5) ± 0.1 × 10(5) M(-1) s(-1) and 3.2 × 10(5) ± 0.3 × 10(5) M(-1) s(-1), respectively). Acyl-CoA synthetase classes involved in cholate catabolism were found in both Actinobacteria and Proteobacteria. Overall, this study provides insight into the physiological roles of acyl-CoA synthetases in steroid catabolism and a phylogenetic classification enabling prediction of specific functions of related enzymes.

Project description:Microbial metabolism is often considered modular, but metabolic engineering studies have shown that transferring pathways, or modules, between organisms is not always straightforward. The Thi5-dependent pathway(s) for synthesis of the pyrimidine moiety of thiamine from Saccharomyces cerevisiae and Legionella pneumophila functioned differently when incorporated into the metabolic network of Salmonella enterica. Function of Thi5 from Saccharomyces cerevisiae (ScThi5) required modification of the underlying metabolic network, while LpThi5 functioned with the native network. Here we probe the metabolic requirements for heterologous function of ScThi5 and report strong genetic and physiological evidence for a connection between alpha-ketoglutarate (αKG) levels and ScThi5 function. The connection was built with two classes of genetic suppressors linked to metabolic flux or metabolite pool changes. Further, direct modulation of nitrogen assimilation through nutritional or genetic modification implicated αKG levels in Thi5 function. Exogenous pyridoxal similarly improved ScThi5 function in S. enterica. Finally, directly increasing αKG and PLP with supplementation improved function of both ScThi5 and relevant variants of Thi5 from Legionella pneumophila (LpThi5). The data herein suggest structural differences between ScThi5 and LpThi5 impact their level of function in vivo and implicate αKG in supporting function of the Thi5 pathway when placed in the heterologous metabolic network of S. enterica. IMPORTANCE Thiamine biosynthesis is a model metabolic node that has been used to extend our understanding of metabolic network structure and individual enzyme function. The requirements for in vivo function of the Thi5-dependent pathway found in Legionella and yeast are poorly characterized. Here we suggest that αKG modulates function of the Thi5 pathway in S. enterica and provide evidence that structural variation between ScThi5 and LpThi5 contributes to their functional differences in a Salmonella enterica host.

Dataset Information

Short-chain fatty acid activation by acyl-coenzyme A synthetases requires SIR2 protein function in Salmonella enterica and Saccharomyces cerevisiae.

Publications

Short-chain fatty acid activation by acyl-coenzyme A synthetases requires SIR2 protein function in Salmonella enterica and Saccharomyces cerevisiae.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets