Streptomyces ATP nucleotide 3'-pyrophosphokinase is an extracellular, ribosome-independent, and stringent factor-mimic ppGpp synthetase with an unusually broad acceptor spectrum. The gene-containing DNA fragments cloned from chromosomal DNA of a producer S. morookaensis into pIJ699 and pUC plasmids were found to express the active enzyme in the transformed S. lividans TK24 and enteric E. coli JM109 and nitrogen-fixing Klebsiella pneumoniae M5a1 and 5022, respectively. Base sequence of the structural gene and the deduced amino acid sequence exhibited little homology to those of E. coli stringent factor and related proteins. Growth retardation was seen in some transformants.