Achromobacter xylosoxydans

Achromobacter xylosoxydans has been used to cany out the selective hydroxylation in high yield, using the enzyme which catalyses the first step in nicotinic acid degradation. The whole-cell biotransformation process has been scaled-up to 12 m, which is sufficient to produce high purity 6-hydroxynicotinic acid for the subsequent chemical reactions. The hydroxylation is oxygen requiring, so that oxygen transfer rate-limits the reaction. 

For the direct hydroxylation of N-heterocycles a microbial oxidation is most suitable. Lonza developed a process to produce 6-hydroxynicotinic acid on a 10 tonnes scale [5]. The enzymatic production is carried out in two-steps. Firstly, Achromobacter xylosoxydans LK1 biomass is produced, which possesses a highly... 

Little is known about the hydroxylation of hetoocyclic substrates, and more experimental work is needed in this area. Achromobacter xylosoxydans (DSM 2783) wad Pseudonumas pudda (NCIB 8176 or 10521) are particularly effective in the hydroxylation of nicotinic acid (107) to 6-hydroxynicotinic acid (108 equation 39), and commercial processes oqrable of giving up to 97% yield have been developed. It is interesting to note that in this case the product is precipitated as it forms by formation of its magnesium or barium salt, and this could serve to protect the product from further degradation as well as facilitating its recovery. 

Organism A. oxydans, Arthrobacter oxydans A. xylosoxydans, Achromobacter xylosoxydans B. subtilis, Bacillus subtilis E. coli, Escherichia coli K. terrigena, Klebsiella terrigena M. neoau-rum, Mycobacter neoaurum O.antropii, Ochrobactrum antropii P. putida, Pseudomonas putida. 6-APA, 6-Aminopenicillanic acid... 

The 3,6-diposition-substituted pyridine compounds are important intermediates for industrial synthesis, especially for production of some agricultural chemicals. This compound can be obtained by chemically synthesized from pyridine, but the process is accompanied by some by-products. Microbial hydroxylation of aromatic compounds is a very efficient method of regioselective reaction. Several methods have been reported for the preparation of 3,6-disubstituted pyridine using microorganisms. In 1985, Lehky et al. reported the microbial production of 6-hydroxynicotinic acid (6-HNA) from nicotinic acid (NA) by Achromobacter xylosoxydans Nagasawa et al. also prepared 6-HNA from NA by using Pseudomonas fluorescens TN5. 

Achromobacterxyiosoxydans subsp. xylosoxydans -Achromobacter ruhlandii -Achromobacter sp. (3-17)... 

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