STUDIES ON THE RELATIONSHIPS BETWEEN NEMATODES AND OTHER SOIL MICROORGANISMS: III. LYTIC ACTION OF SOIL MYXOBACTERS ON CERTAIN SPECIES OF NEMATODES

Abstract

Three species of bacterium-feeding nematodes, Caenorhabditis briggsae, Rhabditis oxycerca, and Panagrellus sp. were lysed by two out of three soil isolates of myxobacters in liquid and agar medium. Aphelenchus avenue, a fungus-feeding nematode and Heterodera trifolii, a cyst-forming plant parasite, were unaffected by the myxobacters. Lysis of the nematodes was also shown spectrophotometrically by the decrease in optical density of a nematode homogenate following addition of an enzyme concentrate from a cell-free fluid culture of one of the myxobacters, and by the increase in trichloracetic acid soluble tyrosine residues in the mixture after 15–20 minutes incubation. The enzyme concentrate could be separated into a "lytic" fraction that dissolved the nematodes and a "proteolytic" fraction that did not.