Structural insights into omega-class glutathione transferases: a snapshot of enzyme reduction and identification of a non-catalytic ligandin site

Glutathione transferases (GSTs) are dimeric enzymes containing one active-site per monomer. The omega-class GSTs (hGSTO1-1 and hGSTO2-2 in humans) are homodimeric and carry out a range of reactions including the glutathione-dependant reduction of a range of compounds and the reduction of S-(phenacyl)glutathiones to acetophenones. Both types of reaction result in the formation of a mixed-disulfide of the enzyme with glutathione through the catalytic cysteine (C32). Recycling of the enzyme utilizes a second glutathione molecule and results in oxidized glutathione (GSSG) release. The crystal structure of an active-site mutant (C32A) of the hGSTO1-1 isozyme in complex with GSSG provides a snapshot of the enzyme in the process of regeneration. GSSG occupies both the G (GSH-binding) and H (hydrophobic-binding) sites and causes re-arrangement of some H-site residues. In the same structure we demonstrate the existence of a novel "ligandin" binding site deep within in the dimer interface of this enzyme, containing S-(4-nitrophenacyl)glutathione, an isozyme-specific substrate for hGSTO1-1. The ligandin site, conserved in Omega class GSTs from a range of species, is hydrophobic in nature and may represent the binding location for tocopherol esters that are uncompetitive hGSTO1-1 inhibitors.This work was supported by National Health and Medical Research Council Project Grant 366731. AJO is supported by an Australian Research Council Future Fellowship FT0990287

A Mark-recapture study of striped bass in the Rappahannock River, Virginia Annual Report 1989-1990

A total of 6,203 striped bass were tagged in fall 1989 and 2,033 in spring 1990 on the Rappahannock River. In fall 1989, 63.5% of the tagged striped bass were less than 400 mm fork length (FL). In comparison, 86% of the fish were greater than 400 mm FL in spring 1990. Pound nets in the Rappahannock River account for 75% of the recaptures, while out of state recaptures account for only 0. 008% of the total returns

A Mark-recapture study of striped bass in the James and Rappahannock Rivers, Virginia Annual Report 1990-1991

A total of 1,903 striped bass were tagged in fall 1990 and 2,708 in spring 1991 on the Rappahannock River. A total of 2,405 striped bass were tagged in fall 1991 on the James River. In fall 1990, 47.2% of the striped bass tagged on the Rappahannock were less than 425 mm fork length (FL). In comparison, only 13.9% of the fish were less than 425 mm FL in spring 1991. Pound nets in the Rappahannock River accounted for 66.3% of the recaptures, while out of state recaptures accounted for only 2.65% of the total returns. In the fall 1990, the mean fork length of striped bass tagged and released in the James River that were captured by haul seines and fyke nets were 44 7 mm and 449 mm, respectively

A survey of weather information possessed by thirty-two pupils randomly selected from sixth and eleventh grades and from special classes

Thesis (Ed.M.)--Boston Universit

Upper bound on the free energy of the spin 1/2 Heisenberg ferromagnet

The authors obtain an upper bound on the free energy of the spin 1/2 Heisenberg ferromagnet. The zero field bound is, at low temperature, similar to the formula given by the magnon approximation. That is, its functional dependence on temperature is the same but the constant is different.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/43209/1/11005_2005_Article_BF01885500.pd

Uniform convergence of the free energy of the classical Heisenberg model to that of the gaussian model

We show that the free energy of the classical Heisenberg model converges to the free energy of the Gaussian in the low-temperature limit. The limit is uniform as the field is taken to zero.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45161/1/10955_2005_Article_BF01329858.pd

On asymptotic limits for the quantum Heisenberg model

The authors discuss various asymptotic limits of the classical and quantum Heisenberg model. They give a new proof that the thermodynamic free energy of the quantum model converges to the free energy of the classical model in the limit of large spins. They also obtain Gaussian and free Bose gas limits for the classical and quantum models respectively.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/48819/2/jav23i14p3199.pd

The developmental biology of <i>Charnia</i> and the eumetazoan affinity of the Ediacaran rangeomorphs.

Molecular timescales estimate that early animal lineages diverged tens of millions of years before their earliest unequivocal fossil evidence. The Ediacaran macrobiota (~574 to 538 million years ago) are largely eschewed from this debate, primarily due to their extreme phylogenetic uncertainty, but remain germane. We characterize the development of Charnia masoni and establish the affinity of rangeomorphs, among the oldest and most enigmatic components of the Ediacaran macrobiota. We provide the first direct evidence for the internal interconnected nature of rangeomorphs and show that Charnia was constructed of repeated branches that derived successively from pre-existing branches. We find homology and rationalize morphogenesis between disparate rangeomorph taxa, before producing a phylogenetic analysis, resolving Charnia as a stem-eumetazoan and expanding the anatomical disparity of that group to include a long-extinct bodyplan. These data bring competing records of early animal evolution into closer agreement, reformulating our understanding of the evolutionary emergence of animal bodyplans