Sains Malaysiana  35(2): 23-28 (2006)

Pengenalpastian Protein Membran Putatif dalam Sporozoit

Eimeria tenella Melalui Penyaringan Imuno

(Identification of Putative Membrane Proteins in Eimeria tenella

Sporozoites by Immunoscreening)

Puay-Eng Soon, Mohd. Sanusi Jangi & Kiew-Lian Wan

Pusat Pengajian Biosains dan Bioteknologi

Fakulti Sains dan Teknologi, Universiti Kebangsaan Malaysia

43600 UKM Bangi, Selangor D.E.

Fiona M. Tomley

Institute for Animal Health

Compton, Newbury, Berkshire RG20 7NN

United Kingdom

ABSTRAK

Dalam parasit intrasel obligat seperti Eimeria tenella, protein membran dipercayai memainkan peranan yang penting dalam pengecaman dan pelekatan pada sel perumah supaya proses penyerangan parasit ke dalam sel perumah dapat disempurnakan. Untuk mengenalpasti protein pada membran E. tenella, penyaringan imuno telah dilakukan dengan menggunakan antiserum terhadap fraksi subsel yang telah diperkayakan dengan protein membran sporozoit. Usaha penyaringan imuno ini berjaya memencilkan 21 klon positif.  Daripada jumlah ini, 13 klon menunjukkan pemadanan bermakna dengan jujukan dalam pangkalan data, iaitu 11 dengan protein mikronem EtMIC4, satu dengan EtMIC1 dan satu lagi dengan EtMIC2. Lapan klon selebihnya yang tidak menunjukkan sebarang pemadanan bermakna dengan jujukan dalam pangkalan data didapati membawa lima gen yang berlainan. Secara keseluruhannya, hasil kajian ini menunjukkan bahawa kaedah penyaringan imuno berupaya mengenalpasti gen baru yang kemungkinan besar mengekodkan protein membran dalam sporozoit E. tenella.

Kata kunci: protein membran; penyaringan imuno; sporozoit

ABSTRACT

In obligate intracellular parasites such as Eimeria tenella,  membrane proteins are believed to play an important role in the identification of and attachment to host cell to facilitate host cell invasion. In order to identify proteins on the membrane of E. tenella, an immunoscreening was carried out using antisera against a subcellular fraction which was enriched with membrane proteins from the sporozoites. This immunoscreening effort successfully isolated 21 positive clones. From this total, 13 clones showed significant matches with sequences in the database, i.e. 11 with the microneme protein EtMIC4, one with EtMIC1 and another with EtMIC2. The remaining eight clones which did not show any significant match with sequences in the database was found to carry five different genes. Overall, results of this study demonstrated that the immunoscreening method is capable of identifying novel genes that are likely to code for membrane proteins in E. tenella sporozoites.

Keywords: membrane protein; immunoscreening; sporozoite 

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