Abstract
Isolates of thermophilic bacteria from desert soil in Kuwait, heavily contaminated with crude oil, have been screened for the presence of restriction endonuclease activity. One of the isolates (B7S), identified as Bacillus stearothermophilus, showed a high level of restriction endonuclease activity when a cell-free extract was incubated with lambda bacteriophage DNA at 65 degrees C. A type II restriction endonuclease (BstB7SI) has been partially purified from this isolate. BstB7SI recognises the six-base sequence RCCGGY (R = A or G; Y = T or C) and hydrolyses the phosphodiester bond in both strands of the DNA substrate between the first and second bases of the recognition sequence 5'-R decreases CCGGY-3'producing four-base 5' overhangs. BstB7SI is therefore an isoschizomer of the mesophilic prototype restriction endonuclease Cfr10I. BstB7SI has a pH optimum of 9.7, requires 10 mM MgCl2 and 75 mM NaCl for maximum activity, and retains full enzyme activity when incubated for 5 min at temperatures up to 70 degrees C.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
