HEAT SHOCK-INDUCED AND ALKALINE PH-INDUCED PROTEINS OF CAMPYLOBACTER-JEJUNI - CHARACTERIZATION AND IMMUNOLOGICAL PROPERTIES

The protein response to physiological stress was characterized in Camp ylobacter jejuni 81176 after exposure to heat and pH shock and followi ng periods of recovery. Immunoreactivities of major stress-related pro teins were determined with anti-Campylobacter immune rabbit serum and intestinal lavage fluid. Distinct proteins with molecular masses rangi ng from 10 to 120 kDa were induced and/or released by selective heat o r pH treatments. The most notable responses were those of two proteins with apparent molecular masses of 45 and 64 kDa that were induced and two other proteins of 10 and 12 kDa that were released by selective h eat shock, alkaline pH treatment, or both. On the basis of N-terminal sequence analysis and immunological crossreactivity data, the 64- and 10-kDa proteins were the C. jejuni homologs of Escherichia coli GroEL and GroES proteins, respectively. Enhanced chemiluminescence Western b lotting (immunoblotting) revealed that all four proteins were among th e major protein antigens recognized by anti-Campylobacter rabbit serum immunoglobulin G (IgG) and immune rabbit intestinal lavage IgA (secre tory IgA). The results of this investigation suggest that the C. jejun i 10-, 12-, 45-, and 64-kDa proteins and a number of minor stress-rela ted proteins deserve further evaluation of their respective roles in C ampylobacter pathogenesis and immunity.