Dunno about specific ions, we measured osmolality of lysed cells (see
our 2004 JBC AlrA paper), its ~ 250 mOsm/ kg H2O for veg cells, and is
400 at 6 hours.  

For cytosolic pH, see Aerts et al 1985 Cell.  We saw cytosolic pH's in
veg cells ranging from 6.4 to 7.4 depending on cell cycle phase (see our
2000 JBC RtoA paper)

Also, be careful with 'Sorenson's phosphate buffer', about 15 years ago
I read a protocol using this  buffer, and didn't have a recipe- I
emailed the Dicty listserver and got ~6 replies.  Each recipe was
different.....

cheers
Richard Gomer
 

Richard Gomer
Professor
TAMU Biology 
ILSB    MS 3474
301 Old Main Drive
College Station, TX  77843-3474
979 458 5745




>>> Ralph Gräf <[log in to unmask]> 06/24/10 6:54 AM >>> 
Dear Dicty Researchers,

I was trying to find a publication where somebody has measured or  
estimated the cytosolic salt concentrations of prominent cations and  
anions but I was not successful. I doubt that the commonly used low  
ionic strength Soerenson phosphate buffer reflects a physiological  
situation for cytosolic proteins.  We would like to use an optimal  
physiological buffer for cytosolic proteins with regard to pH, ion  
concentration and ion composition. Any helpful hints are welcome.

All the best,

Ralph


---------------------------------------------------------

Prof. Dr. Ralph Gräf

University of Potsdam
Institute of Biochemistry and Biology
Department of CELL BIOLOGY

Karl-Liebknecht-Strasse 24-25, Haus 26
14476 Potsdam
Germany

Tel.: +49-(0)331 9775520
FAX: +49-(0)331 9775522

http://www.bio.uni-potsdam.de/professuren/zellbiologie/aktivitaten