Ksilanaz ve β(1,3-1,4)-Glukanaz Enzimlerini Kodlayan Çift Fonksiyonlu Genlerin Gram-Pozitif Bakterilerde Ekspresyonu

Rumen anaerop selulolitik bakterisine ait Ksilanaz ve β(1,3-1,4)-Glukanaz aktivitelerini kodlayan gen, fakültatif anaeropStreptococcus bovis dahil baz› Gram-pozitif bakterilere transfer edilmesi için Escherichia/Streptococcus plasmid vektöre klonland›.Klonlanm›fl genden kaynaklanan enzim aktiviteleri S. bovis’in s›v› kültürlerinde duraklama faz›ndan itibaren düflüfl göstermektedir.Bu düflüfller klonlanm›fl enzimlerin ortamda bulunan birikmifl laktik aside olan duyarl›l›ktan kaynaklanmaktad›r. Klonlanm›fl genaktivitelerinin kültür s›v›s› içine sal›nmas› klon genin iflaret peptidinin Gram-pozitif bakteriler taraf›ndan tan›nd›¤›n› göstermektedir. 

Expression of Bifunctional Genes Encoding Xylanase and b(1,3-1,4)-Glucanase in Gram-Positive Bacteria

The xylanase and b(1,3-1,4)-Glucanase activities encoding gene from the cellulolytic rumen anaerobe bacterium was cloned into Escherichia/Streptococcus shuttle vector for introduction into Gram-positive bacteria, including the rumen facultative anaerobe bacterium Streptococcus bovis. Activities due to the cloned gene decreased in the stationary phase in batch cultures of S. bovis, reflecting the sensitivity of the cloned enzymes to inactivation in the presence of accumulated lactic acid. Cloned gene activity was detected in the culture supernatant, indicating recognition of the cloned gene signal peptide by Gram-positive bacteria.