Two different pathways are involved in the beta-oxidation of n-alkanoic and n-phenylalkanoic acids in Pseudomonas putida U: genetic studies and biotechnological applications
| Autor: | Olivera, Elías R., Carnicero, David, García, Belén, Miñambres Rodríguez, Baltasar, Moreno, Miguel A., Cañedo, Librada M., Dirusso, Concetta C., Naharro, Germán, Luengo, José M. |
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| Jazyk: | angličtina |
| Rok vydání: | 2001 |
| Předmět: | |
| Zdroj: | Digital.CSIC. Repositorio Institucional del CSIC instname |
| ISSN: | 1125-1808 |
| Popis: | 12 pages, 4 figures.-- PMID: 11251808 [PubMed]. In Pseudomonas putida U, the degradation of n-alkanoic and n-phenylalkanoic acids is carried out by two sets of beta-oxidation enzymes (betaI and betaII). Whereas the first one (called betaI) is constitutive and catalyses the degradation of n-alkanoic and n-phenylalkanoic acids very efficiently, the other one (betaII), which is only expressed when some of the genes encoding betaI enzymes are mutated, catabolizes n-phenylalkanoates (n > 4) much more slowly. Genetic studies revealed that disruption or deletion of some of the betaI genes handicaps the growth of P. putida U in media containing n-alkanoic or n-phenylalkanoic acids with an acyl moiety longer than C4. However, all these mutants regained their ability to grow in media containing n-alkanoates as a result of the induction of betaII, but they were still unable to catabolize n-phenylalkanoates completely, as the betaI-FadBA enzymes are essential for the beta-oxidation of certain n-phenylalkanoyl-CoA derivatives when they reach a critical size. Owing to the existence of the betaII system, mutants lacking betaIfadB/A are able to synthesize new poly 3-OH-n-alkanoates (PHAs) and poly 3-OH-n-phenylalkanoates (PHPhAs) efficiently. However, they are unable to degrade these polymers, becoming bioplastic overproducer mutants. The genetic and biochemical importance of these results is reported and discussed. This investigation was supported by (i) Comisión Interministerial de Ciencia y Tecnología, Madrid, grant AMB97-0603-C02-01, (ii) Fondo Europeo de Desarrollo Regional grant 1FD97-0245 and Junta de Castilla y León grant LE 42/96. B.M. and E.R.O. are recipients of fellowships from (i) and (ii) respectively. Thanks are extended to Dr J. L. Fernández (Biomar, Onzonilla, León) for help with the NMR analyses; to Dr M. A. Cortés (Waters Cromatografía, Madrid) for help with the LC-MS determinations, and to Dr J. L. García for critical reading of the manuscript. The nucleotide sequences corresponding to this manuscript have been submitted to the EMBL/GenBank/DDBJ nucleotide sequence data libraries and assigned accession numbers AF150669, AF150672, AF290948, AF 290949 and AF290950. |
| Databáze: | OpenAIRE |
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