Showing papers in "Acta Crystallographica in 2002"

The structure of the FERM domain of merlin, the neurofiromatosis type 2 gene product

Abstract: Neurofibromatosis type 2 is an autosomal dominant disorder characterized by central nervous system tumors. The cause of the disease has been traced to mutations in the gene coding for a protein that is alternately called merlin or schwannomin and is a member of the ERM family (ezrin, radixin and moesin). The ERM proteins link the cytoskeleton to the cell membrane either directly through integral membrane proteins or indirectly through membrane-associated proteins. In this paper, the expression, purification, crystallization and crystal structure of the N-terminal domain of merlin are described. The crystals exhibit the symmetry of space group P2(1)2(1)2(1), with two molecules in the asymmetric unit. The recorded diffraction pattern extends to 1.8A resolution. The structure was solved by the molecular-replacement method and the model was refined to a conventional R value of 19.3% (R(free) = 22.7%). The N-terminal domain of merlin closely resembles those described for the corresponding domains in moesin and radixin and exhibits a cloverleaf architecture with three distinct subdomains. The structure allows a better rationalization of the impact of selected disease-causing mutations on the integrity of the protein.

Asymmetric hydrogen bonds in centrosymmetric environment: Neutron study of very short hydrogen bonds in potassium hydrogen dichloromaleate

Abstract: Asymmetric hydrogen bonds in centrosymmetric environment: Neutron study of very short hydrogen bonds in potassium hydrogen dichloromaleate

Expression, purification and preliminary crystallographic studies of α-amylase isozyme 1 from barley seeds

Abstract: The germinating barley seed contains two major alpha-amylase isozyme families, AMY1 and AMY2, involved in starch degradation to provide energy used by the plant embryo for growth. Many years of difficulty in growing three-dimensional crystals of natural AMY1 have now been overcome by a nonapeptide truncation of the enzyme C-terminus. The truncated enzyme was overexpressed in Pichia pastoris, purified and crystallized by the hanging-drop vapour-diffusion method using polyethylene glycol 8000 as precipitant and 2-propanol as an additive. Crystals belong to the orthorhombic space group P2(1)2(1)2, with unit-cell parameters a = 88.36, b = 72.82, c = 61.74 A and one molecule per asymmetric unit.

Xtrack - a web based crystallographic notebook

Abstract: Xtrack is a web-based database-backed crystallographic notebook system that allows groups of workers to keep track of crystallographic project data from the crystallization stage through to data bank deposition. A working demonstration version is available from http://xray.bmc.uu.se/xtrack and the code is available for those who wish to set up their own databases.

Crystallization and preliminary X-ray analysis of the molybdenum-dependent pyrogallol-phloroglucinol transhydroxylase of Pelobacter acidigallici

Abstract: Crystals of the molybdo-/iron–sulfur protein pyrogallol:phloroglucinol hydroxyltransferase (transhydroxylase; EC 19712) from Pelobacter acidigallici were grown by vapour diffusion in an N2/H2 atmosphere using polyethylene glycol as a precipitant In this microorganism, transhydroxylase converts pyrogallol to phloroglucinol in a unique reaction without oxygen transfer from water Growth of crystals suitable for X-ray analysis was strongly dependent on the presence of dithionite as a reducing agent The crystals belonged to space group P1 and MAD data were collected on the iron K edge to resolutions higher than 25 A

Asymmetric hydrogen bonds in a centrosymmetric environment. II:Neutron study of the very short hydrogen bonds in potassium hydrogen dichloromaleate at 90 K and 170 K.

Abstract: Asymmetric hydrogen bonds in a centrosymmetric environment. II:Neutron study of the very short hydrogen bonds in potassium hydrogen dichloromaleate at 90 K and 170 K.