The homogentisate pathway: a central catabolic pathway involved in the degradation of L-phenylalanine, L-tyrosine, and 3-hydroxyphenylacetate in Pseudomonas putida. Export

@article{citeulike:2707005, abstract = {Pseudomonas putida metabolizes Phe and Tyr through a peripheral pathway involving hydroxylation of Phe to Tyr (PhhAB), conversion of Tyr into 4-hydroxyphenylpyruvate (TyrB), and formation of homogentisate (Hpd) as the central intermediate. Homogentisate is then catabolized by a central catabolic pathway that involves three enzymes, homogentisate dioxygenase (HmgA), fumarylacetoacetate hydrolase (HmgB), and maleylacetoacetate isomerase (HmgC), finally yielding fumarate and acetoacetate. Whereas the phh, tyr, and hpd genes are not linked in the P. putida genome, the hmgABC genes appear to form a single transcriptional unit. Gel retardation assays and lacZ translational fusion experiments have shown that hmgR encodes a specific repressor that controls the inducible expression of the divergently transcribed hmgABC catabolic genes, and homogentisate is the inducer molecule. Footprinting analysis revealed that HmgR protects a region in the Phmg promoter that spans a 17-bp palindromic motif and an external direct repetition from position -16 to position 29 with respect to the transcription start site. The HmgR protein is thus the first IclR-type regulator that acts as a repressor of an aromatic catabolic pathway. We engineered a broad-host-range mobilizable catabolic cassette harboring the hmgABC, hpd, and tyrB genes that allows heterologous bacteria to use Tyr as a unique carbon and energy source. Remarkably, we show here that the catabolism of 3-hydroxyphenylacetate in P. putida U funnels also into the homogentisate central pathway, revealing that the hmg cluster is a key catabolic trait for biodegradation of a small number of aromatic compounds.}, address = {Estaci\'{o}n Agr\'{\i}cola Experimental, Consejo Superior de Investigaciones Cient\'{\i}ficas, Finca Marzanas, 24346 Grulleros, Le\'{o}n, Spain.}, author = {Arias-Barrau, E. and Olivera, E. R. and Luengo, J. M. and Fern\'{a}ndez, C. and Gal\'{a}n, B. and Garc\'{\i}a, J. L. and D\'{\i}az, E. and Mi\~{n}ambres, B.}, citeulike-article-id = {2707005}, citeulike-linkout-0 = {http://dx.doi.org/10.1128/JB.186.15.5062-5077.2004}, citeulike-linkout-1 = {http://view.ncbi.nlm.nih.gov/pubmed/15262943}, citeulike-linkout-2 = {http://www.hubmed.org/display.cgi?uids=15262943}, doi = {10.1128/JB.186.15.5062-5077.2004}, issn = {0021-9193}, journal = {Journal of bacteriology}, keywords = {biodegradation, for-the-review, hmgr, homogentisate, regulation, transcription}, month = {August}, number = {15}, pages = {5062--5077}, posted-at = {2008-07-23 17:23:25}, priority = {3}, title = {The homogentisate pathway: a central catabolic pathway involved in the degradation of L-phenylalanine, L-tyrosine, and 3-hydroxyphenylacetate in Pseudomonas putida.}, url = {http://dx.doi.org/10.1128/JB.186.15.5062-5077.2004}, volume = {186}, year = {2004} }

TY - JOUR ID - citeulike:2707005 L3 - citeulike-article-id:2707005 N2 - Pseudomonas putida metabolizes Phe and Tyr through a peripheral pathway involving hydroxylation of Phe to Tyr (PhhAB), conversion of Tyr into 4-hydroxyphenylpyruvate (TyrB), and formation of homogentisate (Hpd) as the central intermediate. Homogentisate is then catabolized by a central catabolic pathway that involves three enzymes, homogentisate dioxygenase (HmgA), fumarylacetoacetate hydrolase (HmgB), and maleylacetoacetate isomerase (HmgC), finally yielding fumarate and acetoacetate. Whereas the phh, tyr, and hpd genes are not linked in the P. putida genome, the hmgABC genes appear to form a single transcriptional unit. Gel retardation assays and lacZ translational fusion experiments have shown that hmgR encodes a specific repressor that controls the inducible expression of the divergently transcribed hmgABC catabolic genes, and homogentisate is the inducer molecule. Footprinting analysis revealed that HmgR protects a region in the Phmg promoter that spans a 17-bp palindromic motif and an external direct repetition from position -16 to position 29 with respect to the transcription start site. The HmgR protein is thus the first IclR-type regulator that acts as a repressor of an aromatic catabolic pathway. We engineered a broad-host-range mobilizable catabolic cassette harboring the hmgABC, hpd, and tyrB genes that allows heterologous bacteria to use Tyr as a unique carbon and energy source. Remarkably, we show here that the catabolism of 3-hydroxyphenylacetate in P. putida U funnels also into the homogentisate central pathway, revealing that the hmg cluster is a key catabolic trait for biodegradation of a small number of aromatic compounds. IS - 15 JF - Journal of bacteriology SN - 0021-9193 AD - Estación Agrícola Experimental, Consejo Superior de Investigaciones Científicas, Finca Marzanas, 24346 Grulleros, León, Spain. EP - 5077 TI - The homogentisate pathway: a central catabolic pathway involved in the degradation of L-phenylalanine, L-tyrosine, and 3-hydroxyphenylacetate in Pseudomonas putida. VL - 186 SP - 5062 KW - biodegradation KW - for-the-review KW - hmgr KW - homogentisate KW - regulation KW - transcription AU - Arias-Barrau, E AU - Olivera, ER AU - Luengo, JM AU - Fernández, C AU - Galán, B AU - García, JL AU - Díaz, E AU - Miñambres, B PY - 2004/08// UR - http://dx.doi.org/10.1128/JB.186.15.5062-5077.2004 ER -