0.3 - 100 (see comments and method) µm^2/sec
||Lenaz G, Fato R. Is ubiquinone diffusion rate-limiting for electron transfer? J Bioenerg Biomembr. 1986 Oct18(5):369-401. p.384 paragraph 4PubMed ID3021715
||1) Fato R, Battino M, Degli Esposti M, Parenti Castelli G, Lenaz G. Determination of partition and lateral diffusion coefficients of ubiquinones by fluorescence quenching of n-(9-anthroyloxy)stearic acids in phospholipid vesicles and mitochondrial membranes. Biochemistry. 1986 Jun 3 25(11):3378-90. AND (2) Gupte S, Wu ES, Hoechli L, Hoechli M, Jacobson K, Sowers AE, Hackenbrock CR. Relationship between lateral diffusion, collision frequency, and electron transfer of mitochondrial inner membrane oxidation-reduction components. Proc Natl Acad Sci U S A. 1984 May81(9):2606-10.PubMed ID3730366, 6326133
||Using fluorescence quenching corresponding to a diffusion coefficient in the range of 10^–6 cm^2/sec (primary source (1)) the long-range diffusion of a short-chain polar Q derivative measured by fluorescence photobleaching recovery (FRAP) (primary source (2)) is 3×10^–9 cm^2/sec.
||The discrepancy between these results is carefully scrutinized, and is mainly ascribed to the differences in diffusion ranges measured by the two techniques it is proposed that short-range diffusion, measured by fluorescence quenching, is more meaningful for electron transfer than long-range diffusion measured by FRAP
||Ron Milo - Admin