Biotransformation of halogenated 2′-deoxyribosides by immobilized lactic acid bacteria

Abstract: An efficient and green bioprocess is herein reported to obtain halogenated nucleosides by transglycosylation using immobilized lactic acid bacteria (LAB). Lactobacillus animalis ATCC 35046 showed a yield of 95% at 0.5h to synthesize 5-fluorouracil-2′-deoxyriboside (floxuridine). Calcium alginate was the best matrix for whole-cell immobilization by entrapment. Its productivity was 87mg/Lh in a continuous bioprocess. When adsorption techniques were evaluated, DEAE-Sepharose was the support which showed higher microbial load, its productivity being 53mg/Lh. Additionally, this microorganism was able to produce 5-bromouracil-2′-deoxyriboside, 6-chloropurine-2′-deoxyriboside and 6-bromopurine-2′-deoxyriboside. [Copyright &y& Elsevier]