[Study of extracellular antigens by immunodiffusion methods in differentiation of pathogenic burkholderiae].

Isolation and composition comparison of extracellular antigens (ECA) of pathogenic burkholderiae in SDS-PAGE electrophoresis and their use for differentiation of these microorganisms by immunodiffusion methods.60 Burkholderia pseudomallei strains, 14 B. mallei strains, 5 B. thailandensis strains, 4 B. cepacia strains were studied. ECA was obtained by Liu technique on F-agar covered with cellophane. SDS-PAGE electrophoresis was performed in 10% gel by Laemmli, immunodiffusion reaction (IDR) in 1% agarose gel, IDR with live cultures, immunoelectrophoresis (IEPH) was performed by the standard techniques. Sera was obtained by immunizing rabbits with a mixture of ECA and incomplete Freund adjuvant.ECA spectra of typical strains of the studied burkholderiae strains after the electrophoresis in SDS-PAGE stained by silver have 8 - 9 major fractions. ECA electrophoregrams of B. pseudomallei and B. thailandensis had a high similarity. ECA analysis by IDR with antisera against ECA revealed maximum number of cross-reactive ECA (3) between B. pseudomallei B. thailandensis. These strains had only a single crossreactive ECA to B. mallei strain. IDR with live culture and antisera to B. thailandensis ECA revealed ECA in all the B. pseudomallei, B. thailandensis strains and did not reveal those in B. mallei strains. Analysis of electrophoregram obtained with IEPH method of pathogenic burkholderiae ECA with antisera to ECA revealed differences of the composition sufficient for their differentiation.The differences of ECA composition revealed by immunodiffusion methods allowed to develop additional approaches of differentiation ofglanders and melioidosis pathogenic agents.