Aliphatic amidase of Rhodococcus rhodochrous PA-34: Purification, characterization and application in synthesis of acrylic acid

Title:Aliphatic amidase of Rhodococcus rhodochrous PA-34: Purification, characterization and application in synthesis of acrylic acid

Volume: 23 Issue: 2

Author(s): Neerja Thakur, Vijay Kumar, Nirmal Kant Sharma, Shikha Thakur and Tek Chand Bhalla

Affiliation:

Keywords: Acrylamide, acrylic acid, amidase, purification, Rhodococcus rhodochrous PA-34.

Abstract: An intracellular aliphatic amide degrading inducible amidase produced by Rhodococcus rhodochrous PA-34 was characterized and acrylic acid synthesis from acrylamide was carried out using whole cell amidase. A bioprocess was developed at 50 ml fed batch reaction using 400 mM acrylamide feeding at an interval of 30 min resulted in the production of 4 g acrylic acid with volumetric and catalytic productivity of 80 g/l and 19 g/g/h respectively. The amidase of this organism had molecular weight of 40 kDa and was purified to 8.5 fold with 8% yield. This enzyme was active within the temperature range of 30 to 60 °C, with optimum temperature 45 °C and pH 7.5. The Vmax, Km, and kcat of purified amidase were calculated as 250 U/mg protein, 4.5 mM, and 166 sec-1 for acrylamide. The enzyme showed tolerance to metal chelating agent (EDTA) and was strongly inhibited by heavy metal ions Hg2+, Ag2+, Cu2+ and Co2+. R. rhodochrous PA-34 amidase preferentially hydrolyzed small aliphatic toxic amide such as acrylamide. Thus, the amidase of R. rhodochrous PA-34 is promising biocatalyst for the synthesis of industrially important acids and biodegradation of toxic amides.

Cite this article as:

Thakur Neerja, Kumar Vijay, Sharma Kant Nirmal, Thakur Shikha and Bhalla Chand Tek, Aliphatic amidase of Rhodococcus rhodochrous PA-34: Purification, characterization and application in synthesis of acrylic acid, Protein & Peptide Letters 2016; 23 (2) . https://dx.doi.org/10.2174/0929866523666151215105442