A new acylamidase from Rhodococcus erythropolis TA37 can hydrolyze N-substituted amides

Area of Science:

• Biochemistry
• Enzymology
• Microbial Biotechnology

Background:

• Acylamidases are enzymes that hydrolyze amide bonds, playing roles in various biological processes.
• Rhodococcus erythropolis is a bacterium known for its metabolic versatility and potential for producing useful enzymes.
• Understanding novel amidase activities is crucial for biocatalysis and metabolic engineering.

Purpose of the Study:

• To isolate and characterize a new acylamidase from Rhodococcus erythropolis TA37.
• To determine the substrate specificity, optimal conditions, and stability of the novel acylamidase.
• To investigate the enzyme's classification within the amidase family based on its sequence and inhibitor profile.

Main Methods:

• Enzyme isolation and purification from Rhodococcus erythropolis TA37.
• Enzyme characterization including substrate specificity assays, pH/temperature optima, and stability tests.
• N-terminal sequencing and comparison with known amidase sequences.
• Inhibition studies using serine protease and aliphatic amidase inhibitors.

Main Results:

• A novel acylamidase was successfully isolated and characterized.
• The enzyme efficiently hydrolyzes N-substituted acrylamides and acid para-nitroanilides, with lower efficiency on aliphatic amides.
• Optimal activity was observed at pH 7-8 and 55°C, with good thermal stability.
• The enzyme's activity was inhibited by serine protease inhibitors, suggesting a serine active site.
• N-terminal sequence homology indicated the enzyme belongs to a new amidase class.

Conclusions:

• The characterized acylamidase represents a novel enzyme with potential applications in biocatalysis.
• The findings suggest the formation of a new amidase class within the amidase signature family.
• Further research into this enzyme class could expand the toolkit for enzymatic amide bond hydrolysis.