Summary: Fidelity of Thermostable DNA Polymerases

[erfi at eel.sunet.se]

Pyrococcus furiosus (P.fu) was isolated from "geothermally heated marine
sediments in Vulcano, Italy" (Fiala, G., and Stetter, K.O., Arch.
Microbiol. 145, p56-61 (1986)).  Pyrococcus species GB-D was isolated
from the Guaymas Basin hydrothermal vents in the Gulf of California
(Jannasch, H.W. et al. (1992) Applied and Environmental Microbiol 58(11),
p3472-3481).  According to Jannasch et al.  P.GB-D has several similarities
to P.fu (i.e. G/C content, ability to use cystine as an electron acceptor)
but P.fu contains amylolytic enzymes which allow it to utilize carbohydrates,
whereas P.GB-D does not grow on carbohydrate media.  The two strains are
therefore probably different (IMHO, but I'm not a microbiologist).  Having
said that, the DNA polymerases from these two strains probably share
a very high percentage of sequence identity (According to Uemori, T. et al,
(1993) NAR 21(2), p259-265 Pfu and Vent, which is presumably less closely
related to Pfu than Deep Vent, share 74.5% sequence identity).

Thanks to Fritz Roth for the following addition to the summary:

Vent (wt:Thermococcus litoralis):  5.3 x 10-5 errors/bp  (Keohavong et al.,1993)Vent (exo-:T. litoralis):          2.7 x 10-5 errors/bp  (Keohavong et al.,1993)
Reference:  Keohavong, P., Ling, L., Dias, C., and Thilly, W.G. (1993)
            PCR Methods and Applications 2, p288-292.
            Assay:  denaturing gradient gel electrophoresis

Eric First (erfi at eel.sunet.se)