Dear subscribers,
I have recently attempted to introduce GFP gene (from clone pGFP10.1 from
Prasher, no induced mutations) into the malarial parasite Plasmodium
falciparum during its asexual stage (the parasite is in red blood cells). No
fluorescence was ever observed although many experimental conditions were
attempted. Given that there may be many reasons why the protein is not
expressed, or even functional should it be expressed, I am interested in
exploring the possibility that a low oxygen tension would be responsible.
Plasmodia in asexual culture are usually kept in 3% oxygen, although several
clonal lines may be cultured in up to 15-17%. The haemoglobin in the
erythocyte would also be envisaged to "mop up" what oxygen is available. There
are suggestions that although Plasmodia are micro aerophiles they may
actually be faculative anaerobes. They only use their electron transport system
for pyrimidine biosynthesis, not for generating energy, they take ATP from
the erythrocyte (or at least thought to!).
I would ask if anyone has an opinion regarding the possibility that" Plasmodia
find it hard to express a functional GFP as oxygen is lacking?" Is there any idea
of the affinity of GFP for oxygen? Are mutants available for low oxygen
conditions to test this idea?
I would appreciate any comments to the email address below as I am not sure
that I am a subscriber to this network as I have recieved no messages since
joining.
Thankyou
Paul
________________________________________________________________________
Paul Horrocks
Institute of Cell and Molecular Biology
University of Edinburgh
Edinburgh EH9 3JR
Scotland, UK.
Email paulh at bio.srv0.ed.ac.uk
Tel. (+44) 131 650 5395
Fax. (+44) 131 668 3870
Email from Paul Horrocks, ICMB, U.o. Edinburgh
paulh at srv0.bio.ed.ac.uk
