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The pathway intermediate 2-keto-3-deoxy-L-galactonate mediates the induction of genes involved in D-galacturonic acid utilization in Aspergillus niger.

ABSTRACT: In Aspergillus niger, the enzymes encoded by gaaA, gaaB, and gaaC catabolize d-galacturonic acid (GA) consecutively into l-galactonate, 2-keto-3-deoxy-l-galactonate, pyruvate, and l-glyceraldehyde, while GaaD converts l-glyceraldehyde to glycerol. Deletion of gaaB or gaaC results in severely impaired growth on GA and accumulation of l-galactonate and 2-keto-3-deoxy-l-galactonate, respectively. Expression levels of GA-responsive genes are specifically elevated in the ?gaaC mutant on GA as compared to the reference strain and other GA catabolic pathway deletion mutants. This indicates that 2-keto-3-deoxy-l-galactonate is the inducer of genes required for GA utilization.

SUBMITTER: Alazi E

PROVIDER: S-EPMC5488244 | biostudies-literature | 2017 May

REPOSITORIES: biostudies-literature

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The pathway intermediate 2-keto-3-deoxy-L-galactonate mediates the induction of genes involved in D-galacturonic acid utilization in Aspergillus niger.

Alazi Ebru E Khosravi Claire C Homan Tim G TG du Pré Saskia S Arentshorst Mark M Di Falco Marcos M Pham Thi T M TTM Peng Mao M Aguilar-Pontes Maria Victoria MV Visser Jaap J Tsang Adrian A de Vries Ronald P RP Ram Arthur F J AFJ

FEBS letters 20170506 10

In Aspergillus niger, the enzymes encoded by gaaA, gaaB, and gaaC catabolize d-galacturonic acid (GA) consecutively into l-galactonate, 2-keto-3-deoxy-l-galactonate, pyruvate, and l-glyceraldehyde, while GaaD converts l-glyceraldehyde to glycerol. Deletion of gaaB or gaaC results in severely impaired growth on GA and accumulation of l-galactonate and 2-keto-3-deoxy-l-galactonate, respectively. Expression levels of GA-responsive genes are specifically elevated in the ∆gaaC mutant on GA as compare ...[more]

PMID: 28417461

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Evidence for inducer function of 2-keto-3-deoxy-L-galactonate in D-galacturonic acid induced gene expression in Aspergillus niger

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