%0 Journal Article
%A Artmann, G.M.
%A Digel, I.
%A Zerlin, K.F.
%A Maggakis-Kelemen, Ch.
%A Linder, Pt.
%A Porst, D.
%A Stadler, A.M.
%A Kayser, P.
%A Dikta, G.
%A Temiz Artmann, A.
%T Hemoglobin senses body temperature
%J European biophysics journal
%V 38
%@ 0175-7571
%C Berlin
%I Springer
%M PreJuSER-4701
%P 589 - 600
%D 2009
%Z This work was supported by the Ministry of Innovation, Science, Research and Technology of the State of North Rhine-Westphalia to G. M.
%X When aspirating human red blood cells (RBCs) into 1.3 mum pipettes (DeltaP = -2.3 kPa), a transition from blocking the pipette below a critical temperature T(c) = 36.3 +/- 0.3 degrees C to passing it above the T(c) occurred (micropipette passage transition). With a 1.1 mum pipette no passage was seen which enabled RBC volume measurements also above T(c). With increasing temperature RBCs lost volume significantly faster below than above a T(c) = 36.4 +/- 0.7 (volume transition). Colloid osmotic pressure (COP) measurements of RBCs in autologous plasma (25 degrees C < or = T < or = 39.5 degrees C) showed a T (c) at 37.1 +/- 0.2 degrees C above which the COP rapidly decreased (COP transition). In NMR T(1)-relaxation time measurements, the T(1) of RBCs in autologous plasma changed from a linear (r = 0.99) increment below T(c) = 37 +/- 1 degrees C at a rate of 0.023 s/K into zero slope above T(c) (RBC T(1) transition). In conclusion: An amorphous hemoglobin-water gel formed in the spherical trail, the residual partial sphere of the aspirated RBC. At T(c), a sudden fluidization of the gel occurs. All changes mentioned above happen at a distinct T(c) close to body temperature. The T(c) is moved +0.8 degrees C to higher temperatures when a D(2)O buffer is used. We suggest a mechanism similar to a "glass transition" or a "colloidal phase transition". At T(c), the stabilizing Hb bound water molecules reach a threshold number enabling a partial Hb unfolding. Thus, Hb senses body temperature which must be inscribed in the primary structure of hemoglobin and possibly other proteins.
%K Body Temperature
%K Erythrocyte Volume
%K Hemoglobins: chemistry
%K Hemoglobins: metabolism
%K Humans
%K Magnetic Resonance Spectroscopy
%K Osmotic Pressure
%K Phase Transition
%K Temperature
%K Water: metabolism
%K Hemoglobins (NLM Chemicals)
%K Water (NLM Chemicals)
%K J (WoSType)
%F PUB:(DE-HGF)16
%9 Journal Article
%$ pmid:19238378
%U <Go to ISI:>//WOS:000265917300005
%R 10.1007/s00249-009-0410-8
%U https://juser.fz-juelich.de/record/4701