Catalyzes the hydrolysis of short-chain aliphatic amides to their corresponding organic acids with release of ammonia. Efficiently hydrolyzes propionamide, acetamide and acrylamide, but shows a very weak activity with aromatic and longer chain aliphatic amides. Also exhibits in vitro acyl transferase activity, transferring the acyl moiety of short-chain amides to hydroxylamine to form hydroxamates. a monocarboxylic acid amide + H2O = a monocarboxylate + NH4(+) Optimum pH is 7. Optimum temperature is 55 degrees Celsius. Belongs to the carbon-nitrogen hydrolase superfamily. Aliphatic amidase family.