Catalyzes phosphoribosylation of neamine using 5-phosphoribosyl-1-diphosphate (PRPP) as a phosphoribosyl donor to generate 5''-phosphoribostamycin in the biosynthetic pathway of butirosin. 5-phospho-alpha-D-ribose 1-diphosphate + neamine = 5''-phosphoribostamycin + diphosphate Divalent metal ion. Optimum pH is 7.5. Optimum temperature is 27-32 degrees Celsius. Antibiotic biosynthesis; butirosin biosynthesis.