The promoter region of the ß-glucanase gene was identified using a transcriptional fusion between the upstream region of the Streptococcus bovis ß-glucanase gene and the celA gene. | Turk J Biol 25 (2001) 37-44 © T†BÜTAK Expression of a Fungal Cellulase Gene by §-glucanase Promoter of Streptococcus bovis1 Mehmet Sait EKÜNCÜ Kahramanmaraß SŸt•Ÿ Ümam University, Faculty of Agriculture, Department of Animal Science, Kahramanmaraß - TURKEY Received: Abstract : The promoter region of the §-glucanase gene was identified using a transcriptional fusion between the upstream region of the Streptococcus bovis §-glucanase gene and the celA gene. Using the transcriptional and protein localisation signals of the S. bovis §-glucanase gene, an in-frame tarnslational fusion between the end of the §-glucanase signal sequence and the ATG of the Neocallimastix patriciarum celA gene was constructed. The §-glucanase promoter-celA fusion was expressed in both E. coli and S. bovis. The activity of the protein produced was found to be cellassociated in E. coli, it but localised to the supernatant fraction of harvested cells of S. bovis. In this study for the first time we have demonstrated that the promoter of the gene from rumen bacteria can express a fungal gene. Key Words: fungal cellulase, Streptococcus bovis, promoter, gene expression. Introduction The forage plant cell wall is a complex and a fascinating biological structure. It is made up of polymers of cellulose and other noncellulosic polysaccharides, such as xylans and pectins in association with lignin, proteins, ions, and water (1-5). Cellulose hydrolysis is a complex process thought to be carried out by the combined action of different enzymatic activities including endoglucanase, cellobiosidase and §-glucosidase (6-8). In recent years, the molecular biology of bacterial cellulases has received considerable attention (9). There have been many reports of genes being cloned from many of the predominant species of ruminal bacteria, but only recently from the ruminal anaerobic fungi, by Gilbert et al., (10) and Xue et al., (11,12). Although the importance of establishing the structure of rumen .
