A new Thermus sp. class-IIS enzyme sub-family: isolation of a 'twin' endonuclease TspDTI with a novel specificity 5'-ATGAA(N(11/9))-3', related to TspGWI, TaqII and Tth111II.
The TspDTI restriction endonuclease, which shows a novel recognition specificity 5'-ATGAA(N(11/9))-3', was isolated from Thermus sp. DT. TspDTI appears to be a 'twin' of restriction endonuclease TspGWI from Thermus sp. GW, as we have previously reported. TspGWI was isolated from the same location as TspDTI, it recognizes a related sequence 5'-ACGGA(N(11/9))-3' and has conserved cleavage positions. Both enzymes resemble two other class-IIS endonucleases from Thermus sp.: TaqII and Tth111II. N-terminal amino acid sequences of TspGWI tryptic peptides exhibit 88.9-100% similarity to the TaqII sequence. All four enzymes were purified to homogeneity; their polypeptide sizes (114.5-122 kDa) make them the largest class-IIS restriction endonucleases known to date. The existence of a Thermus sp. sub-family of class-IIS restriction endonucleases of a common origin is herein proposed.
Skowron
Piotr M
PM
EURx Ltd, Gdańsk, Poland. piotrs@eurx.com.pl
Majewski
Jarosław
J
Zylicz-Stachula
Agnieszka
A
Rutkowska
Sylwia M
SM
Jaworowska
Izabela
I
Harasimowicz-Słowińska
Renata I
RI
D000595:Amino Acid Sequence; D001483:Base Sequence; D001665:Binding Sites / Q000235:genetics; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D015252:Deoxyribonucleases, Type II Site-Specific / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D019143:Evolution, Molecular; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D013379:Substrate Specificity; D013824:Thermus / Q000201:enzymology* / Q000235:genetics
D004269:DNA, Bacterial; C042367:endodeoxyribonuclease TaqII; C027716:endodeoxyribonuclease Tth111II; D015252:Deoxyribonucleases, Type II Site-Specific