The paper that introduced biochemists to the idea of allosteric feedback inhibition [Monod J, Changeux J-P & Jacob F (1963) J Mol Biol 6, 306-329] is now 50 years old, and the two papers on models for enzyme cooperativity that followed it [Monod J, Wyman J & Changeux J-P (1965) J Mol Biol 12, 88-118; Koshland DE, Némethy G & Filmer D (1966) Biochemistry 5, 365-385] are almost as old. All of the...

The method to be described for the determination of hemoglobin depends upon the comparison, in a calorimeter, of carbon monoxide hemoglobin solutions, one of which has a known hemoglobin content. Hoppe-Seyler (1) was the first to describe carbon monoxide hemoglobin and to make use of this stable combination for estimating the hemoglobin content of blood. He devised a “double pipette” for compar...

We investigate the one-dimensional Kondo lattice model (1D KLM) for ferromagnetic Kondo couplings. The so-called ferromagnetic 2-leg spin ladder and the S=1 antiferromagnet occur as new one-dimensional Kondo insulators. Both exhibit a spin gap. But, in contrast to the strong coupling limit, the Haldane state which characterizes the 2-leg spin ladder Kondo insulator cannot fight against very wea...

The method to be described for the determination of hemoglobin depends upon the comparison, in a calorimeter, of carbon monoxide hemoglobin solutions, one of which has a known hemoglobin content. Hoppe-Seyler (1) was the first to describe carbon monoxide hemoglobin and to make use of this stable combination for estimating the hemoglobin content of blood. He devised a “double pipette” for compar...

H+ titration studies on oxygenated and deoxygenated haemoglobins from carp, rainbow trout, spiny dogfish and pig are reported, and compared with Hb-H+ equilibria in other species and structural information deduced from amino acid sequences. The buffer values of oxygenated and deoxygenated teleost haemoglobins are low in comparison with elasmobranch and mammalian haemoglobins. This correlates wi...

JOHN Maynard Smith was one of the most influential After that, his allegiance gradually faded, and he left the party in 1956 following the brutal Soviet suppression evolutionary biologists of the generation that succeeded the “founding fathers” of population genetof the Hungarian revolution (Maynard Smith 1985). In later years, he became a critic of Marxism, while ics, as he was fond of calling...

Trapping quaternary structures of hemoglobin in single crystals or by encapsulation in silica gels has provided a demanding set of data to test statistical mechanical models of allostery. In this work, we compare the results of those experiments with predictions of the four major allosteric models for hemoglobin: the quaternary two-state model of Monod, Wyman, and Changeux; the tertiary two-sta...

To understand why the classical two-state allosteric model of Monod, Wyman, and Changeux explains cooperative oxygen binding by hemoglobin but does not explain changes in oxygen affinity by allosteric inhibitors, we have investigated the kinetic properties of unstable conformations transiently trapped by encapsulation in silica gels. Conformational trapping reveals that after nanosecond photodi...

Between 1957 and 1959, Arthur Pardee, François Jacob, and Jacques Monod [5] conducted a set of experiments at the Pasteur Institute in Paris, France, that was later called the PaJaMa Experiments, a moniker derived from the researchers' last names. In these experiments, they described how genes [6] of a species of single-celled bacteria, called Escherichia coli [7] (E. coli ), controlled the pro...