Isolation and molecular identification of bacteria producing cholesterol oxidase enzymes in Northwest Iran

Background and Objective: Cholesterol is one of the most important element which is used to make many essential body metabolites, such as sex hormone and vitamin D .However is one of the most important causative factors of atherosclerosis, ،cerebral thrombosis, ،hypertension،peripheral vascular disease ،coronary heart disease and Alzheimer. Therefore, a quick, inexpensive and reliable way to determine the amount of cholesterol is very important. Cholesterol oxidase enzyme is a monomeric enzyme that has the ability to detect cholesterol levels. So identifying a suitable and dynamic method for providing this enzyme naturally can be very fruitful. Since some bacteria have the ability to produce this particular enzyme, the focus of this study is isolation and molecular identification of bacteria producing the cholesterol oxidase enzyme in the northwest of Iran. Materials and Methods: In this practical study, 100 soil samples from 5 different cities in north western Iran were collected in 1996.After culture, the bacteria were identified by microbial and biochemical tests. To confirm the activity of colonies producing cholesterol oxidase, colorimetric and browning methods were used. Finally, extraction of RNA from positive samples was done and PCR 16s rRN technique was used to confirm the strain obtained. SPSS1 software was used for statistical analysis. Result: Out of 100 samples examined, only 8 samples of the bacteria producing the cholesterol oxidase enzyme were identified, which all of 8 samples were from agricultural soil samples. Also, in the browning and colour test, the activity of both cholesterol oxidases was confirmed. Based on differential tests of microbiology, the bacteria producing cholesterol oxidase enzyme were Brevibacillus DCY35 type. At the end, the molecular identity of these strains was confirmed by the confirmation of the 16srRNA sequence. Also, the cholesterol oxidase enzyme’s hormones were detected in both the intracellular and extracellular forms. Conclusion: The results of the study indicated that the Brevibacillus DCY35 bacteria in the north western region of Iran have the ability to produce cholesterol oxidase enzymes extracellularly and intracellularly.

کلیدواژه ها:

cholesterol oxidase enzyme ، 16srRNA ، Brevibacillus DCY35