Objective:To investigate the banding patterns of whole cell protein(WCP) and outer membrane protein (OMP) of Burkholderia pseudomallei(B.pseudomallei) in clinical isolates from patients with melioidosis. Methods:WCP and OMP of of B.pseudomallei in 50 clinical isolates,from 47 patients with melioidosis were prepared and separated by polyacrylamide gel electrophoresis(SDS-PAGE) using 10%gels and stained with Coomassie brilliant blue.The banding patterns were compared by using a laser densitometer and dendrogram. Results:There were 6 different banding patterns of WCP and 2 types of OMP.Type 1 -5 WCP had 8 common protein bands at 19.0 - 45.0 kDa with identical OMP pattern.The banding patterns of WCP in type 6 were distinct from the others and also its OMP profile.The majority of clinical isolates(37/50,74%) were in type 1 WCP.Of the remaining isolates,8 were in type 2,2 in type 3,and one each was in type 4 to 6.There was no significant association between the WCP typing and the demographic or clinical features of the investigated patients.Conclusion:Despite the wide variation of clinical features of melioidosis,the results of this study show that B.pseudomallei had a few differences in the WCP and OMP profiles.Therefore typing of WCP and OMP,using SDS-PAGE analysis,could be an alternative method for phenotypic differentiation in clinical isolates of B.pseudomallei. Objective: To investigate the banding patterns of whole cell protein (WCP) and outer membrane protein (OMP) of Burkholderia pseudomallei (B. pseudomallei) in clinical isolates from patients with melioidosis. Methods: WCP and OMP of B. pseudomallei in 50 clinical isolates from 47 patients with melioidosis were prepared and separated by polyacrylamide gel electrophoresis (SDS-PAGE) using 10% gels and stained with Coomassie brilliant blue. The banding patterns were compared by using a laser densitometer and dendrogram. Results: There were 6 different banding patterns of WCP and 2 types of OMP.Type 1-5 WCP had 8 common protein bands at 19.0-45.0 kDa with identical OMP pattern. The banding patterns of WCP in type 6 were distinct from the others and also its OMP profile. majority of clinical isolates (37/50, 74%) were in type 1 WCP.Of the remaining isolates, 8 were in type 2, 2 in type 3, and one each was in type 4 to 6. There was no significant association between the WCP typing and the demographic or clinical features of the investigated patients. Confc: Despite the wide variation of clinical features of melioidosis, the results of this study show that B. pseudomallei had a few differences in the WCP and OMP profiles. Before in typing of WCP and OMP, using SDS -PAGE analysis, could be an alternative method for phenotypic differentiation in clinical isolates of B. pseudomallei.