The extracellular nucleases commonly called the BAL 31 nuclease take their name from the designation given the marine bacterium producing them, which was originally classified asPseudomonasBAL 31 (1 ) and reclassified as belonging to the small genusAlteromonas(2 ) with the species namedespejianaafter its discoverer, a Chilean microbiologist. The nuclease activities were originally found as contaminants in preparations of bacteriophage PM2 grown on this organism, but were shown (3 ,4 ) to be bacterial products. Only 10–20% of the nuclease activity is found in the periplasm (5 ). The American Type Culture Collection strain ofAlteromonas espejiana(ATCC 29659) produces BAL 31 nuclease as proficiently as the strain originally obtained from its discoverer.
