PROJE BAŞLIĞI: GLUTAMİNAZ VE ÜREAZ İÇERMEYEN ANTİTÜMÖR ETKİLİ LASPARAGİNAZ ÜRETEN MİKROORGANİZMALARIN İZOLASYONU KAREKTERİZASYONU VE ENZİM ÜRETİM OPTİMİZASYONU

L-asparaginase (EC. 3.5.1.1, L-asparagine amidohydrolase), which is one of

the leading enzymes of industrial importance and used in cancer treatment,

has attracted great attention in the pharmacology sector in recent years.

In our study, different bacteria were isolated and purified from the

digestive systems of some animals and from the soil. By comparing the L-

asparaginase activities of the isolates with the zones they formed on the

M9 medium, bacteria were selected for the highest L-asparaginase production

potential. It was later determined whether these bacteria produce

glutaminase and urease. The isolates that produce glutaminase and L-

asparaginase that do not produce glutaminase and urease were determined by

sequencing Bacillus atrophaeus strain AspK1 (MW866485.1), Bacillus atrophaeus

strain AspK3 (MW872009.1) and Brevibacterium frigoritolerans strain AspS1

(MW866486.1) 16s rRNA. Among them, Bacillus atrophaeus strain AspK1 was found

to have the highest L-asparaginase activity (15.2 U/mL), and studies were

continued with this organism. The effects of carbon and nitrogen sources,

pH, temperature and incubation time on enzyme production were investigated.

L-asparaginase was first partially purified by ethanol precipitation, then

it could be purified by anion exchange chromatography. The purity of the

enzyme was checked by SDS-PAGE analysis and its molecular weight was

determined to be 42 kDa. The optimum temperature of the enzyme was found to

be 30 ℃, and the optimum pH to be 7. The effects of various substances on

L-asparaginase activity have been studied and it has been observed that

Mg 2+ , Ca 2+ and Mn 2+ ions increase the activity.