To access your account, log in or register.	shopping cart | log in

FAVORITE TOOLS Enzyme Finder NEBcutter NEBuffer Chart Double Digest Finder Isoschizomers DNA Sequences and Maps REBASE

Home > Products > Restriction Endonucleases > Restriction Endonucleases > PstI > FAQ PstI FAQ See the Restriction Endonucleases FAQ also. Q1: When is star activity a problem for PstI? Q2: Does spermidine increase activity? Q3: Are there specific surrounding sequences that produce slow or resistant sites? Q4: Is PstI inhibited by dUTP incorporated at the site? Q5: What is the molecular weight of PstI? Q6: Is PstI blocked by methylation? Q7: What is the activity of PstI at 25°C? Q8: Is PstI used in special techniques? Q1: When is star activity a problem for PstI? A1: Conditions of high pH, low salt, high glycerol; 8% DMSO can cause star activity. (Malyguine et al. (1980). Gene 8: 163-177). Q2: Does spermidine increase activity? A2: No, 0.5-2mM spermidine inhibits digestion by PstI (Kuosmanen and Poso (1985). FEBS Lett. 179: 17-20. Spermidine suppresses star activity of PstI (Pingoud (1985). Eur. J. Biochem. 147:150-109. Q3: Are there specific surrounding sequences that produce slow or resistant sites? A3: The presence of adjacent runs of G-C base pairs confers significant resistance to cleavage. Armstrong and Bauer (1982). NAR 10: 993-1007. Q4: Is PstI inhibited by dUTP incorporated at the site? A4: Yes. 100% dUTP incoporation reduces PstI cleavage to 25%. Glenn et al. (1994). Biotechniques 17: 1086-1090. Q5: What is the molecular weight of PstI? A5: The molecular weight of PstI is 37.37 kDa based on sequence data. Q6: Is PstI blocked by methylation? A6: PstI is not blocked by Dam, Dcm or CpG methylation. It will not cut AGCTGCAG when methylated by AluI methylase. Q7: What is the activity of PstI at 25°C? A7: PstI is 50-75% active at 25°C. Q8: Is PstI used in special techniques? A8: Yes, PstI is used for DNA typing.