Search anything and hit enter
  • Teams
  • Members
  • Projects
  • Events
  • Calls
  • Jobs
  • publications
  • Software
  • Tools
  • Network
  • Equipment

A little guide for advanced search:

  • Tip 1. You can use quotes "" to search for an exact expression.
    Example: "cell division"
  • Tip 2. You can use + symbol to restrict results containing all words.
    Example: +cell +stem
  • Tip 3. You can use + and - symbols to force inclusion or exclusion of specific words.
    Example: +cell -stem
e.g. searching for members in projects tagged cancer
Search for
Count
IN
OUT
Content 1
  • member
  • team
  • department
  • center
  • program_project
  • nrc
  • whocc
  • project
  • software
  • tool
  • patent
  • Administrative Staff
  • Assistant Professor
  • Associate Professor
  • Clinical Research Assistant
  • Full Professor
  • Graduate Student
  • Lab assistant
  • Non-permanent Researcher
  • Permanent Researcher
  • Pharmacist
  • PhD Student
  • Physician
  • Post-doc
  • Project Manager
  • Research Associate
  • Research Engineer
  • Retired scientist
  • Technician
  • Undergraduate Student
  • Veterinary
  • Visiting Scientist
  • Deputy Director of Center
  • Deputy Director of Department
  • Deputy Director of National Reference Center
  • Deputy Head of Facility
  • Director of Center
  • Director of Department
  • Director of Institute
  • Director of National Reference Center
  • Group Leader
  • Head of Facility
  • Head of Operations
  • Head of Structure
  • Honorary President of the Departement
  • Labex Coordinator
Content 2
  • member
  • team
  • department
  • center
  • program_project
  • nrc
  • whocc
  • project
  • software
  • tool
  • patent
  • Administrative Staff
  • Assistant Professor
  • Associate Professor
  • Clinical Research Assistant
  • Full Professor
  • Graduate Student
  • Lab assistant
  • Non-permanent Researcher
  • Permanent Researcher
  • Pharmacist
  • PhD Student
  • Physician
  • Post-doc
  • Project Manager
  • Research Associate
  • Research Engineer
  • Retired scientist
  • Technician
  • Undergraduate Student
  • Veterinary
  • Visiting Scientist
  • Deputy Director of Center
  • Deputy Director of Department
  • Deputy Director of National Reference Center
  • Deputy Head of Facility
  • Director of Center
  • Director of Department
  • Director of Institute
  • Director of National Reference Center
  • Group Leader
  • Head of Facility
  • Head of Operations
  • Head of Structure
  • Honorary President of the Departement
  • Labex Coordinator
Search
Go back
Scroll to top
Share
© Research
Publication : The EMBO journal

E. coli DNA polymerase I as a reverse transcriptase

Scientific Fields
Diseases
Organisms
Applications
Technique

Published in The EMBO journal - 01 Feb 1993

Ricchetti M, Buc H

Link to Pubmed [PMID] – 7679988

EMBO J. 1993 Feb;12(2):387-96

The ability of Escherichia coli DNA polymerase I to retrotranscribe an RNA template was examined under steady-state conditions, using a primer extension assay which allows determination of kinetic constants on well-defined heterogeneous sequences. Equilibrium and rate constants for the initial binding step of the enzyme to two homologous DNA and RNA templates do not show striking differences. In both cases, under steady-state conditions, processivity limits the maximal velocity of the translocation process. The lower catalytic efficiency of the enzyme when it operates on RNA is then reflected by a 100-fold greater apparent average Michaelis constant for the deoxynucleotide substrates. We conclude that E.coli DNA polymerase I effectively transcribes both templates, its performances being limited in both cases by its intrinsically low processivity. Furthermore, DNA polymerase I is a strikingly accurate enzyme when operating on RNA. Magnesium has to be substituted by manganese so that a pattern of errors could be detected. This great accuracy results from a combination of factors. The 3′ to 5′ exonuclease activity is still operating but in a non-discriminative manner. Elongation of a mismatched primer terminus is markedly impaired. The forward polymerization rate of incorporation of an incorrect deoxynucleotide must be extremely low, when Mg2+ is present. In summary E.coli DNA polymerase I preserves its main characteristics when retrotranscribing RNA.

http://www.ncbi.nlm.nih.gov/pubmed/7679988