Highly Enantioselective Biohydrolysis of sec‐Alkyl Sulfate Esters with Inversion of Configuration Catalysed by Pseudomonas spp.

Abstract

In search of highly enantioselective microbial sec-alkyl sulfatase activity, a broad screening among bacteria, fungi and Archaea revealed several Ralstonia and Pseudomonas spp. as valuable sources, whereas fungi were completely inactive. In particular, Pseudomonas sp. DSM 6611 was able to hydrolyse the (R) enantiomers of a broad range of rac-sec-alkyl

Inverting hydrolases and their use in enantioconvergent biotransformations

“…The first highly selective inverting sec -alkyl sulfatase was Pisa1 from Pseudomonas DSM 6611, the structure of which has recently been elucidated [40]. The reaction rates for Pisa1 were much higher than for biotransformations with whole cells of this organism [38] and reached the critical 50% threshold for many substrates in kinetic resolution experiments. Inversion of configuration was proven by reactions with enantiopure substrates and, in addition, by labeling studies, which showed exclusive incorporation of 18 O in the product alcohol using 18 O-labeled buffer [17].…”

Enzymes that catalyse SN2 reaction mechanisms

“…They also showed by [ 18 O]-water labelling experiments that the oxygen from water became incorporated into the resultant alcohol, thus these enzymes catalyse C-O bond rather than S-O bond cleavage, and have been termed inverting sulfatases. 82 There has been a renewed interest in these enzymes as potential biocatalysts for the preparation of enantiomerically pure secondary alcohols. 82,84 Other bacteria have been screened, and inverting sulfatases have been identified in, for example, Paracoccus denitrificans, Synechococcus, Rhodococcus ruber and Sulfolobus acidocaldarius, capable of a relatively wide substrate range of primary and secondary alkylsulfate displacements.…”

“…82 There has been a renewed interest in these enzymes as potential biocatalysts for the preparation of enantiomerically pure secondary alcohols. 82,84 Other bacteria have been screened, and inverting sulfatases have been identified in, for example, Paracoccus denitrificans, Synechococcus, Rhodococcus ruber and Sulfolobus acidocaldarius, capable of a relatively wide substrate range of primary and secondary alkylsulfate displacements. Presumably the reaction mechanism involves an S N 2 displacement at carbon of the sulfate group by hydroxide.…”

Structure and mechanism of an inverting alkylsulfatase from Pseudomonas sp. DSM6611 specific for secondary alkyl sulfates

“…In a search for a more stable alternative, extended screening for secondary alkylsulfatase activity was performed among pseudomonads and close relatives thereof, and revealed Pseudomonas sp. DSM6611 as the most promising candidate . This strain was isolated from soil for its ability to degrade halogenated aromatic compounds, such as 4‐fluorobenzoate .…”