Supathra Tiewchaloren, Virach Junnu, Jeerawan Ongrotchanakun 
Department of Parasitology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand 

Abstract 
SDS-PAGE is considered to be a supplementary and basic method for the identification of Naegleria fowleri. This method was used to determine the molecular weight of three specimens of pathogenic Naegleria spp. from: Siriraj, Ramathibodi and Chachoengsao isolated from fatal Thai patients with primary amebic meningoencephalitis. This study revealed that all of the three pathogenic Naegleria spp. showed some similarity in molecular weight (14.4-94 kDa). In contrast, the molecular weight of the reference strain (14.4-64 kDa) showed some individual molecular weight (94, 67, 52, 43, 40.6, 28.5, 26.5 and 20.4 kDa) difference from the three pathogenic Naegleria species. This result demonstrated that the pathogenic strains have a few protein components distinct from the reference strains. Keywords: SDS-PAGE, pathogenic Naegleria spp.