PRODUCTION OF α -AMYLASE FROM ARCHAEAL SOURCE Azade Attar 1 , G urbet Ejder 1 , Y eliz Başaran-Elalmış 1 , S evil Yücel 1 , M eral Birbir 2 1 - Department of Bioengineering , Yıldız Technical University, Istanbul, Turkey 2 - Department of Biology, Marmara University, Istanbul, Turkey 2011 Biochimie Biochemistry Poster 2
Enzymes are protein structured molecules which catalyze biochemical reactions on mild conditions.
Enzymes that found wide and extensive research topic in medicine, biochemistry and biology have got into daily and economical life. Among these enzymes, α-amylase (EC.22.214.171.124) is a commonly used one in industry.
Leaning to wide microbial biodiversity of Turkey we investigated archaebacterial isolates which produce carbohydrate hydrolyzing enzymes in extremely salty environments, hence have biotechnological importance.
In this study, α-amylase enzyme of Haloarcula hispanica 2TK2 strain isolat ed in 2004 from Tuzköy Salt Mine of Turkey was used.
Enzyme production capacity of Haloarcula hispanica 2TK2 strain was determined and the activity of archaeal α-amylase was characterized.
Poster 2 Fig.2 Phylogenetic tree of life. 1. INTRODUCTION
Enzyme activity w as determined by DNS assay using starch as substrate.
The effects of buffer and salt concentration to the enzyme activity were investigated for Haloarcula hispanica 2TK2 isolate.
I nvestigated phosphate buffer concentrations were 0.01, 0.02, 0.05, 0.07 and 0.1 M while NaCl concentrations were 0.001, 0.003, 0.006, 0.009, 0.012 and 0.015M.
Poster 2 2. Materials and Methods Fig.4 Picture of reaction tubes taken after α -amylase activity assay.
3.1 Optimum buffer and NaCl concentrations for α -amylase isolate d from Haloarcula hispanica 2TK2 strain Poster 2 3. Results Table 1. The effect of sodium phosphate buffer concentration on α-amylase activity. Table 2. The effect of sodium chloride concentration on α-amylase activity. BUFFER (M) ABS (540 nm) 0,01 0,600 0,02 0,651 0,05 0,270 0,07 0,307* (precipitation) 0,1 0,350* ( precipitation ) 0,110 0,012 NaCl (M) ABS (540 nm) 0,001 0,330 0,003 0,340 0,006 0,437 0,009 0,220 0,015 0,090
3.2 Enzyme activity depending on Haloarcula hispanica 2TK2 i ncubation period Samples used in enzyme assay were taken between 2nd and 6th weeks of incubation. Maximum activity values were obtained in the 5th week of incubation. Poster 2 3. Results Fig.5 Time versus relative activity graph. 3.3 The effect NaCl concentration The effect of NaCl concentration (3 - 5 M) to enzyme activity in the presence and absence of 20% (w/v) starch during microbial production. The highest α -amylase activity was obtained from Haloarcula hispanica 2TK2 culture containing 5 M NaCl with 20% starch. Fig.6 Growth medium variables versus relative activity graph.
Haloarcula hispanica 2TK2 strain grow in high salt concentrations therefore it was expected that α -amylase obtained from this strain may have high activity in the presence of high salt concentration. When the effect of sodium chloride concentration on α-amylase activity was investigated maximum activity values obtained in 0,006M NaCl containing test tubes (Table 2) which is parallel with the literature.
The highest enzyme activity obtained from growth media containing 5 M NaCl with starch at the 5 th week of microbial incubation (Fig. 5) .
Haloarcula hispanica will be a source of a microorganism promising in industry due to its new defined halophilic structure and high thermostability.
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