This family consists of bacterial antibiotic resistance proteins, which confer resistance to various aminoglycosides they include: aminoglycoside 3'-phosphotransferase or kanamycin kinase / neomycin-kanamycin phosphotransferase and streptomycin 3''-kinase or streptomycin 3''-phosphotransferase. The aminoglycoside phosphotransferases inactivate aminoglycoside antibiotics via phosphorylation. This family also includes homoserine kinase. This family is related to fructosamine kinase pfam03881.