(L-glutamyl)(n)-gamma-L-glutamyl-L-glutamyl-[tubulin] + L-glutamate + ATP <=> (L-glutamyl)(n+1)-gamma-L-glutamyl-L-glutamyl-[tubulin] + ADP + phosphate + H(+)
(l-glutamyl)(n)-gamma-l-glutamyl-l-glutamyl-[tubulin] + l-glutamate + atp <=> (l-glutamyl)(n+1)-gamma-l-glutamyl-l-glutamyl-[tubulin] + adp + phosphate + h(+)