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The mimivirus genome encodes a mitochondrial carrier that transports dATP and dTTP

Magnus Monné1, Alan J Robinson, Christoph Boes

  • 1Dunn Human Nutrition Unit, Medical Research Council, Hills Road, Cambridge CB2 2XY, United Kingdom.

Journal of Virology
|January 19, 2007
PubMed

Insights

Giant viruses, like Mimivirus, can possess unique proteins. Researchers found a Mimivirus protein that transports deoxynucleotides, suggesting a novel viral strategy for host replication.

Area of Science:

  • Biochemistry
  • Virology
  • Molecular Biology

Background:

  • Mitochondrial carrier family proteins are crucial for metabolite transport across the inner mitochondrial membrane in eukaryotes.
  • These proteins link cytosolic and mitochondrial metabolic pathways.
  • Previously, these proteins were exclusively found in eukaryotes.

Purpose of the Study:

  • To investigate the function of a mitochondrial carrier family protein encoded by the giant virus Mimivirus.
  • To determine the transport capabilities of this viral protein.

Main Methods:

  • The Mimivirus protein was expressed in the bacterium Lactococcus lactis.
  • Transport assays were performed to identify the substrates transported by the viral protein.

Main Results:

  • The viral protein was successfully expressed in Lactococcus lactis.
  • The protein demonstrated the ability to transport deoxynucleotide triphosphates: dATP and dTTP.
  • The Mimivirus genome is rich in adenine and thymine.

Conclusions:

  • The Mimivirus encodes a functional mitochondrial carrier protein capable of transporting deoxynucleotides.
  • This viral protein likely facilitates the uptake of deoxynucleotides from the host cell's mitochondria.
  • This mechanism may support the replication of the large, AT-rich Mimivirus genome.

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