Screening, cultivation, and biocatalytic performance of Rhodococcus boritolerans FW815 with strong 2,2-dimethylcyclopropanecarbonitrile hydratase activity

Abstract

In this work, a mild, efficient bioconversion of 2,2-dimethylcyclopropanecarbonitrile (DMCPCN) to 2,2-dimethylcyclopropanecarboxamide (DMCPCA) in distilled water system was developed. The isolate FW815 was screened using the enrichment culture technique, displaying strong DMCPCN hydratase activity, and was identified as Rhodococcus boritolerans based on morphological, physiological, biochemical tests and 16S rRNA gene sequencing. Cultivation outcomes indicated that R. boritolerans FW815 was a neutrophile, with a growth optimum of 28-32°C; its DMCPCN hydratase belonged to the Fe-type family, and was most active at 38-42°C, pH 7.0, with maximal activity of 4.51 × 10(4) U g(-1) DCW. R. boritolerans FW815 was found to be DMCPCA amidase-negative, eliminating the contamination of dimethylcyclopropanecarboxylic acid. Moreover, it displayed high activity and acceptable reusability in the non-buffered distilled water system, comparable to those in pH 7.0 phosphate buffer (50.0 mmol l(-1)).

Highly regioselective and efficient production of 1-cyanocyclohexaneacetamide byRhodococcus aetherivoransZJB1208 nitrile hydratase

“…(A)). These results indicated that R. aetherivorans ZJB1208 NHase preferred a slightly acidic environment, which was different from most other reported NHases, but similar to nitrilase from R. rhodochour K22 …”

A simple, efficient and rapid screening technique for differentiating nitrile hydratase and nitrilase producing bacteria

“…Among the microorganisms, bacteria are potent producers of nitrile hydrolyzing enzymes. A number of screening techniques like HPLC, GC, UV spectrophotometer have been reported in the past, to identify microorganisms producing nitrile hydrolyzing enzymes [18,19]. However, these techniques are tedious, time consuming and expensive.…”

Rhodococcus as a Versatile Biocatalyst in Organic Synthesis

“…The hydrolysis of aromatic and arylalkyl nitriles was intensively studied and proven successful for pyridyl-, pyrazinyl-, (substituted) benzyl-, furyl-, and thionyl-moieties [128,129,130,131,132,133] as well as trans-2,3-epoxy-3-aryl-propannitriles [134] or rac -mandelonitrile [135]. R. boritolerans FW815 was shown to have a strong 2,2-dimethyl-c-propanecarbonitrile (DMCPCN) hydratase activity in the absence of amidase activity, leading to an enrichment of 2,2-dimethyl-c-propanecarboxamide (DMCPCA)—an important precursor for the drug cilastatin, which is an inhibitor of a renal peptidase that is involved in the metabolism of other drugs, thereby making these other, combined drugs more effective [136]. Dinitriles are also accepted substrates: whole-cells of Rhodococcus sp.…”

“…ECU1013 (RhEst1) was shown to hydrolyze rac -ethyl-2,2-dimethyl- c -propanecarboxylate ( 94 , rac-DMCPCM) to give ( S )-(+)-2,2-dimethyl-c-propylcarboxylic acid ( 96 , ( S )-DMCPCA)—a valuable precursor in the synthesis of the drug cilastatin ( 97 ) (Scheme 24) [214,215]. This shows an alternative route to cilastatin compared to the previously mentioned nitrile hydratase-catalyzed process starting with 2,2-dimethyl-c-propanecarbonitrile [136].…”