Molecular and Morphological Identification of Balamuthia mandrillaris ( Free- living Amoeba ) Isolated From Environmental Sources in Thi- Qar province / Iraq

Document Type : Primary Research paper


1 Department of Biology , College of Science . University of Thi-Qar

2 Department of Biology , College of Science . University of Basrah


Balamuthia mandrillaris is a free- living amoeba that lives in soil and water near human settlements . It was supposed to occupy the same ecological habitats of Acantamoeba . B. mandrillaris has been reported as the causative agent of fatal Balamuthia Amoebic Encephalitis (BAE )essentially, there is a little information about this genus. So that, this study attempted to determent characterization of B. mandrillaris at molecular level and morphological features. Seventy five of environmental samples were collected from different sources in Thi-Qar province south Iraq during the period February to September 2020. Samples were screened for B. mandrillaris and identified by morphologically and genetically by PCR method. Results stated that B. mandrillaris cyst and trophozoite were observed in some environmental sample were 12 (16%). There was only 9 ( 12% )were positive out of 12 suspected environmental isolates that confirmed by the presence of distinct amoeba cyst or both trophozoites and cyst by using PCR method including Balamuthia mandrillaris specific primer Balspec 16S forward and reverse that amplified a portion of mitochondrial rRNA gene yield a 1075 bp product . Trophozoite and cyst were observed in culture ,the trophozoite stage approximately 35-50 micron in diameter. it has finger like pseudopodia the trophozoite showed an ability to produce pseudopodia from any part of the amoebic body , the cysts of B. mandrillaris were spherical and approximately 12-25 micron surrounded by a double layer membrane , an inner wall that was endocyst and an outer wrinkled wall that was ectocyst. the ectocyst had no pores like Acanthamoeba and endocyst without arms . The presence of B. mandrillaris can be considered a health hazard , as B. mandrillaris is an opportunistic amoeba and also may harbor some pathogenic bacteria .