Stability engineering of the Geobacillus stearothermophilus alcohol dehydrogenase and application for the synthesis of a polyamide 12 precursor was written by Kirmair, Ludwig;Seiler, Daniel Leonard;Skerra, Arne. And the article was included in Applied Microbiology and Biotechnology in 2015.Category: esters-buliding-blocks This article mentions the following:
The thermostable NAD+-dependent alc. dehydrogenase from Geobacillus stearothermophilus (BsADH) was exploited with regard to the biocatalytic synthesis of 锠?oxo lauric acid Me ester (OLAMe), a key intermediate for biobased polyamide 12 production, from the corresponding long-chain alc. Recombinant BsADH was produced in Escherichia coli as a homogeneous tetrameric enzyme and showed high activity towards the industrially relevant substrate 锠?hydroxy lauric acid Me ester (HLAMe) with KM = 86娓璏 and 44 U mg-1. The equilibrium constant for HLAMe oxidation to the aldehyde (OLAMe) with NAD+ was determined as 2.16 鑴?10-3 from the kinetic parameters of the BsADH-catalyzed forward and reverse reactions. Since BsADH displayed limited stability under oxidizing conditions, the predominant oxidation-prone residue Cys257 was mutated to Leu based on sequence homol. with related enzymes and computational simulation. This substitution resulted in an improved BsADH variant exhibiting prolonged stability and an elevated inactivation temperature Semi-preparative biocatalysis at 60鎺矯 using the stabilized enzyme, employing butyraldehyde for in situ cofactor regeneration with only catalytic amounts of NAD+, yielded up to 23% conversion of HLAMe to OLAMe after 30 min. In contrast to other oxidoreductases, no overoxidn. to the dodecanoic diacid monomethyl ester was detected. Thus, the mutated BsADH offers a promising biocatalyst for the selective oxidation of fatty alcs. to yield intermediates for industrial polymer production In the experiment, the researchers used many compounds, for example, 12-Methoxy-12-oxododecanoic acid (cas: 3903-40-0Category: esters-buliding-blocks).
12-Methoxy-12-oxododecanoic acid (cas: 3903-40-0) belongs to esters. Esters perform as high-grade solvents for a broad array of plastics, plasticizers, resins, and lacquers, and are one of the largest classes of synthetic lubricants on the commercial market. Polyesters are important plastics, with monomers linked by ester moieties. Esters contain a carbonyl center, which gives rise to 120鎺?C閳ユ弲閳ユ彊 and O閳ユ弲閳ユ彊 angles. Unlike amides, esters are structurally flexible functional groups because rotation about the C閳ユ彊閳ユ弲 bonds has a low barrier. Their flexibility and low polarity is manifested in their physical properties; they tend to be less rigid (lower melting point) and more volatile (lower boiling point) than the corresponding amides. Category: esters-buliding-blocks
Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics