*Department of Biochemistry, University of Kuwait, P.O. Box 5969, Kuwait; and **Culture
Collection Research, Northern Regional Research Center, Peoria, Illinois. 61604, U.S.A.
ABSTRACT
About 450 isolates of aerobic, mesophilic and thermodurant streptomycetes were obtained from the rhizosphere of flowering planls: Cyperus conglomerotus Rottb., Citrullus colocynthis (L.) Schrad. and Mollkiopsis ciliata Forssk. These plants were growing in a sandy desert exposed to high temperature from natural gas flares in the Magwa oil fields of Kuwait. Of these isolates, 173 were identified as Streptomyces alhus, 167 as S. griseus or S. venezuelae, 24 as S. lavendulae, 5 as S. grarninofaciens, 11 as S. JIaveolus and 67 as S. diastaticus. Thirteen isolates contained meso diaminopimelic acid in their whole-cell hydrolysate, hencc they are not streptomycetes or streptoverticillia. Four hundred and thirty-five isolates were able to grow in the presence o 10-15% sodium chloride solution and 240 grew at 450C, 187 exhibited antibacterial activity, and 93 showed antifungal activity.