Metabolism of the Lathyrus sativus L. Neurotoxin, β-N-Oxalyl-L-α, β-diaminopropionic Acid, by a Pure Culture of a Soil-borne Microbe

Pure cultures of bacteria capable of utilizing the Lathyrus sativus L. neurotoxin, β-N-oxalyl-L-α, β-diaminopropionic acid (ODAP), as their sole carbon and nitrogen source have been isolated from soil-sludge filtrates. Three independent isolates, designated BYA1, BYT1, and BYK1, were selected by repetitive growth on the neurotoxin and purified based upon their antibiotic resistance. Of the three isolates, strain BYA1 demonstrated the highest capacity for ODAP utilization, degrading greater than 98% of the ODAP present in the culture media within 12 h. Using a variety of morphological and biochemical criteria BYA1 was identified as an Enterobacter cloacae. The bacterium harbors a single large plasmid (designated pBYA1) approximately 40–50 kb in size that contains the genetic information for ODAP utilization and antibiotic resistance. Transformation experiments with E. coli recipient strains were used to further define the location of the sequences involved in ODAP metabolism.