Enables malonate-semialdehyde dehydrogenase (acetylating) activity; methylmalonate-semialdehyde dehydrogenase (acylating) activity; and thiolester hydrolase activity. Involved in beta-alanine catabolic process; thymine catabolic process; and valine catabolic process. Predicted to be located in nucleoplasm. Predicted to be active in mitochondrion. Orthologous to human ALDH6A1 (aldehyde dehydrogenase 6 family member A1). [provided by Alliance of Genome Resources, Apr 2022]