Catalyzes the ATP-dependent phosphorylation of maltose to maltose 1-phosphate. Is involved in a branched alpha-glucan biosynthetic pathway from trehalose, together with TreS, GlgE and GlgB (By similarity). ATP + D-maltose = ADP + alpha-maltose 1-phosphate + H(+) Glycan biosynthesis; glycogen biosynthesis. Monomer. Belongs to the aminoglycoside phosphotransferase family.