Disease relevance of BNA5

• Cloning, sequence, and expression of kynureninase from Pseudomonas fluorescens [1].
• The resultant plasmid was used to transform E. coli DH5alpha F', and these cells overexpressed kynureninase to about 37% of total soluble protein [1].

High impact information on BNA5

• We have identified the genes that encode the enzymes of the kynurenine pathway and for BNA5 (YLR231c) and BNA6 (YFR047c) confirmed that they encode kynureninase and quinolinate phosphoribosyl transferase respectively [2].
• Based on this alignment, we predict that Lys227 and Asp212 in P. fluorescens kynureninase are involved in pyridoxal-5'-phosphate binding [1].
• Alignment of the four sequences shows a highly conserved region which corresponds to the pyridoxal-5'-phosphate (PLP) binding site of rat kynureninase [1].
• P. fluorescens kynureninase also exhibits significant homology to the nifS gene product, cysteine desulfurase, and to eucaryotic serine/pyruvate aminotransferases, suggesting that it is a member of subgroup IV of the aminotransferase family of PLP-dependent enzymes [1].
• Hemin added to the medium enhanced total niacin production by increasing the amount of tryptophan metabolized via the kynureninase flux [3].

Associations of BNA5 with chemical compounds

• 2-3H liberation increased dose-dependently at tryptophan concentration higher than 10(-5)M, while the kynureninase flux reached its plateau at 10(-5)M [4].
• Of kynurenine (0.05 mM) added to the medium, 55% went through the transaminase flux (2-H liberation), 20% through the kynureninase flux, but none through the acetyl-CoA flux [5].

References