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Picolinic acid (PA) is a typical mono-carboxylated pyridine derivative produced by human/animals or microorganisms which could be served as nutrients for bacteria. Most <i>Bordetella</i> strains are pathogens causing pertussis or respiratory disease in humans and/or various animals. Previous studies indicated that <i>Bordetella</i> strains harbor the PA degradation <i>pic</i> gene cluster. However, the degradation of PA by <i>Bordetella</i> strains remains unknown. In this study, a reference strain of genus <i>Bordetella</i>, <i>B. bronchiseptica</i> RB50, was investigated. The organization of <i>pic</i> gene cluster of strain RB50 was found to be similar with that of <i>Alcaligenes faecalis</i>, in which the sequence similarities of each Pic proteins are between 60% to 80% except for PicB2 (47% similarity). The 3,6-dihydroxypicolinic acid (3,6DHPA) decarboxylase gene (<i>BB0271</i>, designated as <i>picC_RB50</i>) of strain RB50 was synthesized and over-expressed in <i>E. coli</i> BL21(DE3). The PicC_RB50 showed 75% amino acid similarities against known PicC from <i>Alcaligenes faecalis</i>. The purified PicC_RB50 can efficiently transform 3,6DHPA to 2,5-dihydroxypyridine. The PicC_RB50 exhibits optimal activities at pH 7.0, 35 °C, and the <i>K_m</i> and <i>k_cat</i> values of PicC_RB50 for 3,6DHPA were 20.41 ± 2.60 μM and 7.61 ± 0.53 S⁻¹, respectively. The present study provided new insights into the biodegradation of PA by pathogens of <i>Bordetella</i> spp.