Cell wall formation. ATP + L-alanine + UDP-N-acetyl-alpha-D-muramate = ADP + H(+) + phosphate + UDP-N-acetyl-alpha-D-muramoyl-L-alanine Cell wall biogenesis; peptidoglycan biosynthesis. Belongs to the MurCDEF family. The gene is frameshifted. However, transcriptional slippage at poly(A) may correct the reading frame, which can potentially yield full-length protein.