Sains Malaysiana, 2006;35:23-30.

Abstract

We report here the isolation and sequence analysis of a cDNA fragment for an endoglucanase gene from Aspergillus terreus SUK-I. A pair of primers was designed based on conserved regions of endoglucanase gene. Amplification of A. terreus SUK-I cDNA using the primers produced a DNA band of 642 bp. The cDNA fragment was purified and cloned into pCR®ll-TOPO plasmid vector. The cDNA insert was designated as SA2 and sequenced. Analysis of the SA2 sequence showed a high degree of identity towards endoglucanase gene sequences from A. aculeatus, A kawachii and Talaromyces emersonii. While, the putative amino acid sequence of SA2 showed 74 % identity towards endoglucanase protein from Thermoascus aurantiacus and 69 % identity towards endoglucanase protein from A. kawachii, A. niger, A. aculeatus and A. nidulans. A 66 % identity between SA2 putative amino acid sequence and A. oryzae endoglucanase protein sequence was also observed. Therefore, we concluded that SA2 codes for a putative endoglucanase gene of A. terreus SUK-I.
[Kami melaporkan di sini pemencilan dan analisis satu fragmen cDNA untuk gen endoglukanase daripada Aspergillus terreus SUK-I. Sepasang pencetus telah direkabentuk berasaskan kepada kawasan terpelihara gen endoglukanase. Amplifikasi cDNA A. terreus SUK-I menggunakan pencetus berkenaan menghasilkan satu jalur DNA bersaiz 642 pb. Fragmen cDNA berkenaan telah ditulenkan dan diklonkan ke dalam vektor plasmid pCR®II-TOPO. cDNA selitan telah dilabelkan sebagai SA2 dan dijujukkan. Analisis terhadap jujukan SA2 menunjukkan sebahagian daripada jujukan SA2 mempunyai darjah identiti yang tinggi terhadap jujukan gen endoglukanase daripada A. aculeatus, A. kawachii dan Talaromyces emersonii. Sementara, jujukan asid amino putatif SA2 menunjukkan identiti sebanyak 74% terhadap protein endoglukanase daripada Thermoascus aurantiacus dan identiti sebanyak 69% terhadap protein endoglukanase daripada A. kawachii, A. niger, A. aculeatus dan A. nidulans. ldentiti sebanyak 66% juga diperhatikan di antara jujukan asid amino putatif SA2 dan jujukan protein endoglukanase A. oryzae. Oleh itu, kami membuat kesimpulan bahawa SA2 mengkodkan gen putative endoglukanase A. terreus SUK-I].