Improvement in 5'-position-selective glucosylation of pyridoxine by Verticillium dahliae TPU 4900.
Optimization of culture and reaction conditions for 5'-position-selective transglucosylation to pyridoxine by Verticillium dahliae TPU 4900 was investigated. V. dahliae TPU 4900 had high transglucosylation activity when grown with soluble starch as a carbon source and organic nitrogens such as Esusan meat as a nitrogen source at 15-20 degrees C. Both the yield of pyridoxine 5'-alpha-D-glucoside (PN-5'-alpha-G) and the 5'-position-selectivity reached a maximum when an intact-cell reaction was done at 50-60 degrees C and pH 7 with additions of dextrin. The transglucosylation activity in culture broth was 71 times with the optimization of culture conditions that under the conditions used for screening. The productivity of PN-5'-alpha-G synthesis was 6.9 times that under the initial conditions when the reaction conditions of intact cells were optimized. From 1000 mM (206 g/L) pyridoxine hydrochloride, PN-5'-alpha-G was synthesized to the concentration of 300 mM (98.4 g/L as PN-5'-alpha-G) with 5'-selectivity of 85% in 53 h by intact cells of V. dahliae TPU 4900.
Biotechnology Research Center, Toyama Prefectural University, 5180 Kurokawa, Kosugi, Toyama 939-0398, Japan. k-wada@daiichi-fcj.co.jp
Koichi
K
Wada
Yasuhisa
Y
Asano
D002244:Carbon / Q000378:metabolism; D003470:Culture Media / Q000737:chemistry / Q000378:metabolism; D003912:Dextrins / Q000494:pharmacology; D005959:Glucosidases / Q000378:metabolism; D005960:Glucosides / Q000096:biosynthesis / Q000737:chemistry; D005964:Glucosyltransferases / Q000378:metabolism; D006031:Glycosylation; D006863:Hydrogen-Ion Concentration; D008828:Microbiological Techniques / Q000379:methods; D009584:Nitrogen / Q000378:metabolism; D011736:Pyridoxine / Q000737:chemistry* / Q000378:metabolism*; D013379:Substrate Specificity; D013696:Temperature; D013997:Time Factors; D020172:Verticillium / Q000166:cytology / Q000254:growth & development / Q000378:metabolism*
D003470:Culture Media; D003912:Dextrins; D005960:Glucosides; D002244:Carbon; D005964:Glucosyltransferases; D005959:Glucosidases; D011736:Pyridoxine; D009584:Nitrogen