CORRELATION OF SPECIATION WITH LYTIC RESPONSES OF THE ACHROMOBACTER

Surdy, Theodore E. (Purdue University, Lafayette, Ind.) and S. E. Hartsell. Correlation of speciation with lytic responses of the Achromobacter. J. Bacteriol. 85:1011-1016. 1963.-Lysozymic lysis of six species of Achromobacter was investigated. Three of the six species were lysed with 33, 50, or 100 mug/ml of lysozyme; if higher concentrations of lysozyme were used, precipitation of cells occurred. "Insensitive" cells could be sensitized by the addition of potassium hydroxide, n-butanol, steapsin, or urea, as demonstrated by the subsequent addition of lysozyme. Not all species were sensitive to these agents in the same degree; hence, a spectrum was obtained after the use of the pretreating agents and lysozyme. Optimal clearing of suspensions was observed when cells were suspended in pH 6.6 physiological saline or 0.15 m phosphate buffer and incubated at 45 C. Heat treatment (75 C for 10 min) or freezing (-32 C) and thawing (room temp, 25 C) for one cycle did not increase the sensitivity of the cells to lysozyme. Injury to the cells was evident by the increased amount of lysis noted after pretreatment with potassium hydroxide. When cells were frozen and thawed for three cycles, four of the six species were sensitive to the action of lysozyme. Isolated cell walls elicited a similar lytic pattern to that of whole cells. Individuality of the lytic response of the species (from most sensitive to least sensitive-A. aquamarinus, A. butyri, A. viscosus, A. parvulus, A. guttatus, A. hartlebii) produced a separation scheme. Exhaustive tests proved it to be stable and reliable for these species. The organisms were identified, with the use of the separation scheme, by a person initially unfamiliar with the scheme or the culture.