Some Comments on the Crystallography and the Evolution of the Catalytic Structure in Some Serine Hydrolases

X-ray analysis has provided a 3-dimensional structural basis through which the complex processes of biochemistry and biology can be investigated and understood. The crystallographic studies on the serine hydrolases have provided accurate structures for many of the enzyme families and have shown that although the families evolved independently, their active atoms in their catalytic structures have equivalent stereochemistry. There has also been remarkable variation in the amino acid composition of the catalytic structures. Analysis has shown that their essential catalytic chemistry is achieved through the interactions of carboxyl or carbonyl oxygens, a base and a potential nucleophile. Finally the evolutionary changes in some enzyme families, such as the Ntn-hydrolases, are so extensive that their evolutionary relationships can only be detected by comparisons of their 3-dimensional structures. Thus X-ray analysis gives the biologist Chemical, functional and evolutionary insight into protein molecules

Structure of the T6 Human Nickel Insulin Derivative at 1.35 Å Resolution

This paper presents results of the structural investigation on the human insulin hexamer derivative stabilised by nickel coordination. Single crystals of the Ni-insulin derivative were prepared by the hanging drop vapour diffusion crystallisation method using metal-free insulin and nickel(II) acetate tetrahydrate. The low-temperature crystal structure was determined by the single crystal X-ray crystallographic method with data extending to 1.35 Å spacing. The investigated insulin derivative exhibits the T6 form of insulin and crystallizes in the trigonal system in space group R3, with the unit cell parameters a = b = 81.41 Å and c = 33.75 Å. There are two nickel atoms per insulin hexamer and both are octahedrally coordinated by three Nε2 atoms of three symmetry-related HisB10/HisD10 and three oxygen atoms of three symmetry-related water molecules

Catalysis in Penicillin G Amidase - a Member of the Ntn (N Terminal Nucleophile) Hydrolase Family

The Ntn (N terminal nucleophile) hydrolases are a new family of hydrolytic enzymes with a characteristic fold in their catalytic domain. These enzymes act on a range of substrates, cleaving amide or ester bonds by a nucleophilic reaction. The catalytic nucleophile is the oxygen in serine or threonine side chains, or sulphur in the cysteine side chain. The active site is often created by autocatalytic cleavage at the nucleophile-containing catalytic residue. As a result of cleavage a free alpha amino group is generated which is an essential component in the enzyme’s catalytic structure. The crystal structure of the precursor of the enzyme penicillin amidase has been determined, revealing the stereochemistry at the scissile bond prior to autocatalytic cleavage

The malaria parasite egress protease SUB1 is a calcium-dependent redox switch subtilisin.

Malaria is caused by a protozoan parasite that replicates within an intraerythrocytic parasitophorous vacuole. Release (egress) of malaria merozoites from the host erythrocyte is a highly regulated and calcium-dependent event that is critical for disease progression. Minutes before egress, an essential parasite serine protease called SUB1 is discharged into the parasitophorous vacuole, where it proteolytically processes a subset of parasite proteins that play indispensable roles in egress and invasion. Here we report the first crystallographic structure of Plasmodium falciparum SUB1 at 2.25 Å, in complex with its cognate prodomain. The structure highlights the basis of the calcium dependence of SUB1, as well as its unusual requirement for interactions with substrate residues on both prime and non-prime sides of the scissile bond. Importantly, the structure also reveals the presence of a solvent-exposed redox-sensitive disulphide bridge, unique among the subtilisin family, that likely acts as a regulator of protease activity in the parasite

Duck Valley Resident Fish Stocking Program, 2000 Final Annual Report.

The Shoshone-Paiute Tribes fish-stocking program was begun in 1988 and is intended to provide a subsistence fishery for the tribal members. The program stocks catchable and fingerling size trout in Mt. View and Sheep Creek Reservoirs. Rainbow trout are purchased from only certified disease-free facilities to be stocked in our reservoirs. This project will help restore a fishery for tribal members that historically depended on wild salmon and steelhead in the Owyhee and Bruneau Rivers and their tributaries for their culture as well as for subsistence. This project is partial substitution for loss of anadromous fish production due to construction and operation of hydroelectric dams on the Columbia and Snake Rivers. Until anadromous fish can be returned to the Owyhee and Bruneau Rivers this project will continue indefinitely. As part of this project the Shoshone-Paiute Tribes will also receive income in the form of fees from non-tribal members who come to fish these reservoirs. Regular monitoring and evaluation of the fishery will include sampling for length/weight/condition and for signs of disease. A detailed Monitoring and evaluation plan has been put in place for this project. However due to budget limitations on this project only the fishery surveys and limited water quality work can be completed. A creel survey was initiated in 1998 and we are following the monitoring and evaluation schedule for this program (as budget allows) as well as managing the budget and personnel. This program has been very successful in the past decade and has provided enjoyment and sustenance for both tribal and non-tribal members. All biological data and stocking rates will be including in the Annual reports to Bonneville Power Administration (BPA)

Water molecules as structural determinants among prions of low sequence identity

AbstractThe nature of the factors leading to the conversion of the cellular prion protein (PrPC) into its amyloidogenic isoform (PrPSc) is still matter of debate in the field of structural biology. The NMR structures of non-mammalian PrPC (non-mPrP) from frog, chicken and turtle [Calzolai, L., Lysek, D.A., Perez, D.R., Guntert, P. and Wuthrich, K. (2005) Prion protein NMR structures of chickens, turtles, and frogs. Proc. Natl. Acad. Sci. USA 102, 651–655] have provided some new and valuable information on the scaffolding elements that preserve the PrPC folding, despite their low sequence identity with the mammalian prions (mPrP). The present molecular dynamics study of non-mPrPC focuses on the hydration properties of these proteins in comparison with the mammalian ones. The data reveal new insights in the PrP hydration and focus on the implications for PrPC folding stability and its propensity for interactions. In addition, for the first time, a role in disfavoring the PrPC aggregation is suggested for a conserved β-bulge which is stabilized by the local hydration