A novel metabolic pathway for N-Methylpyrrolidone degradation in Alicycliphilus sp. BQ1.

A novel metabolic pathway for N-Methylpyrrolidone degradation in Alicycliphilus sp. BQ1. Appl Environ Microbiol. 2017 Oct 13;: Authors: Solís-González CJ, Domínguez-Malfavón L, Vargas-Suárez M, Gaytán I, Cevallos MÁ, Lozano L, Cruz-Gómez MJ, Loza-Tavera H Abstract The molecular mechanisms underlying the biodegradation of N-Methylpyrrolidone (NMP), a widely used industrial solvent that produces skin irritation in humans, and is teratogenic in rats, are unknown. Alicycliphilus sp. BQ1 degrades NMP. By studying a transposon-tagged mutant unable to degrade NMP, we identified a six-gene cluster (nmpABCDEF), transcribed as a polycistronic mRNA, encoding enzymes involved in NMP biodegradation. nmpA and the transposon-affected gene nmpB encode a N-methylhydantoin amidohydrolase that would transform NMP to γ-N-methylaminobutyric acid; this would be metabolized by an aminoacid oxidase (NMPC), either by demethylation to produce γ-aminobutyric acid (GABA), or by deamination to produce succinate semialdehyde (SSA). Whether GABA was produced, the activity of a GABA aminotransferase (GABA-AT), not encoded in the nmp gene cluster, would be needed to generate SSA. SSA would be transformed by succinate semialdehyde dehydrogenase (SSDH) (NMPF) to succinate, which enters the Krebs cycle. The ability to consume NMP and to utilize it for growth was complemented in the mutant with nmpABCD genes. Similarly, Escherichia coli MG1655, which has two S...
Source: Applied and Environmental Microbiology - Category: Microbiology Authors: Tags: Appl Environ Microbiol Source Type: research