TY - JOUR AU - Artmann, G.M. AU - Digel, I. AU - Zerlin, K.F. AU - Maggakis-Kelemen, Ch. AU - Linder, Pt. AU - Porst, D. AU - Stadler, A.M. AU - Kayser, P. AU - Dikta, G. AU - Temiz Artmann, A. TI - Hemoglobin senses body temperature JO - European biophysics journal VL - 38 SN - 0175-7571 CY - Berlin PB - Springer M1 - PreJuSER-4701 SP - 589 - 600 PY - 2009 N1 - This work was supported by the Ministry of Innovation, Science, Research and Technology of the State of North Rhine-Westphalia to G. M. AB - 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. KW - Body Temperature KW - Erythrocyte Volume KW - Hemoglobins: chemistry KW - Hemoglobins: metabolism KW - Humans KW - Magnetic Resonance Spectroscopy KW - Osmotic Pressure KW - Phase Transition KW - Temperature KW - Water: metabolism KW - Hemoglobins (NLM Chemicals) KW - Water (NLM Chemicals) KW - J (WoSType) LB - PUB:(DE-HGF)16 C6 - pmid:19238378 UR - <Go to ISI:>//WOS:000265917300005 DO - DOI:10.1007/s00249-009-0410-8 UR - https://juser.fz-juelich.de/record/4701 ER -