Abstracts Category : Other

Effects of the Vibrio alkaline phosphatase variants D12W and T112A-R113G on its promiscuous activity as sulfatase.

by Baldvinsdttir 1993 Flra

Alkaline phosphatases (APs) are enzymes that work as very efficient catalysts with broad substrate specificity. They are primarily phosphomonesterases and play a fundamental role in many types of biological processes such as basic metabolism and gene expression. APs have ability to perform different activities than its native activity which is called promiscuity and previous experiments have shown that changes in the enzyme can affect the promiscuity. In this project the aim was to look at how the T112A-R113G and D12W mutation on the cold-active Vibrio alkaline phosphatase affects its sulfatase promiscuous activity. The D12W variant was studied to see how its kinetic efficiency, with and without NaCl, and heat stability compared with the wild-type (wt). Results indicated that the D12W VAP variant has higher heat stability but lower kinetic values than its wt, which indicates that the variant is less flexible. They also indicated that NaCl affects enzyme catalytic efficiency. Its sulfatase promiscuous activity was practically non-existent and its native activity was very low as well. The T112A-R113G variant had lower phosphatase activity and higher sulfatase activity than its wt, which indicates that concentration of salt in the solution does promote sulfatase activity. Alkalskir fosfatasar (AP) eru ensm sem eru mjg gir hvatar og breivirkir. eir eru aalega fosfmnesterasar og gegna grundvallarhlutverki mrgum tegundum lffrilegra ferla eins og undirstu efnaskipta og genatjningu. AP geta hvata nnur efnahvrf til vibtar vi upprunalega efnahvarfi. a er kalla fjlvirkni og fyrri rannsknir hafa snt a breytingar ensmi getur haft hrif fjlvirkni ess. essu verkefni var skoa hvernig T112A-R113G og D12W stkkbreytingar kuldavirka Vibrio alkalska fosfatasa (VAP) hfu hrif fjlvirkni hans. Gerar voru tilraunir D12W afbriginu til a sj hvernig hreyfiorka, me og n NaCl, og hitastugleiki ess vri mia vi upprunalega ensmi (wt). Niurstur benda til ess a D12W VAP afbrigi hafi meiri hitastugleika en minni hreyfiorku en wt sem gefur til kynna a afbrigi s minna sveigjanlegt. r benda einnig til ess a NaCl hafi hrif hvatavirkni ensmsins. Slfatasa fjlvirkni ess var nstum engin og aalvirkni ess var einnig mjg lg. T112A-R113G afbrigi hafi lgri fosfatasa virkni en hrri slfatasa virkni en wt, sem gefur til kynna a salt styrkur lausninni hafi hrif til hknau slfatasa virkni.