Topic
Multiple isomorphous replacement
About: Multiple isomorphous replacement is a research topic. Over the lifetime, 508 publications have been published within this topic receiving 53542 citations.
Papers published on a yearly basis
Papers
TL;DR: A new triclinic crystal form of human serum albumin (HSA), derived either from pool plasma or from a Pichia pastoris expression system, was obtained from polyethylene glycol 4000 solution, and three-dimensional structures of pHSA and rHSA were determined.
Abstract: A new triclinic crystal form of human serum albumin (HSA), derived either from pool plasma (pHSA) or from a Pichia pastoris expression system (rHSA), was obtained from polyethylene glycol 4000 solution. Three-dimensional structures of pHSA and rHSA were determined at 2.5 A resolution from the new triclinic crystal form by molecular replacement, using atomic coordinates derived from a multiple isomorphous replacement work with a known tetragonal crystal form. The structures of pHSA and rHSA are virtually identical, with an r.m. s. deviation of 0.24 A for all Calpha atoms. The two HSA molecules involved in the asymmetric unit are related by a strict local twofold symmetry such that the Calpha atoms of the two molecules can be superimposed with an r.m.s. deviation of 0.28 A in pHSA. Cys34 is the only cysteine with a free sulfhydryl group which does not participate in a disulfide linkage with any external ligand. Domains II and III both have a pocket formed mostly of hydrophobic and positively charged residues and in which a very wide range of compounds may be accommodated. Three tentative binding sites for long-chain fatty acids, each with different surroundings, are located at the surface of each domain.
1,764 citations
TL;DR: The method demonstrates a remarkable effectiveness for overcoming the phase ambiguity problem that has the major obstacle in the use of SIR or SAS data alone for macromolecular studies.
Abstract: Publisher Summary The chapter presents a procedure that is applicable to single isomorphous replacement (SIR) data without anomalous scattering information as well as to pure single-wavelength anomalous scattering (SAS) data alone, and it does not require the presence of noncrystallographic symmetry. Test results shows that it is very effective; not only can it remove the phase ambiguity but it will also refine the phases at the same time. In actual application to SIR data, the method has even produced results that appear to be superior to those obtained from the multiple isomorphous replacement method. One of the situations in which the phase ambiguity problem occurs is when the isomorphous replacement method is applied to a noncentrosymmetric structure using only one isomorphous data set. The method demonstrates a remarkable effectiveness for overcoming the phase ambiguity problem that has the major obstacle in the use of SIR or SAS data alone for macromolecular studies. The computer programs used in the studies has been assembled into a program package.
1,083 citations
1 Jan 2000
TL;DR: In this article, the authors provide an introduction to protein structure research and highlight the importance of the "all proteins are created equal" principle in protein conformation analysis, and the content of the book focuses on the crystallographic and multidimensional NMR studies.
Abstract: This chapter provides an introduction to research in protein structure. In 1950s there was a complete lack of research on the molecular structure of globular proteins and enzymes. Moreover, there was no information on protein conformation. In the mid 1930s, however, with the study of hemoglobin structure by Max Perutz, research in this field improved dramatically. The phase problem was a major hindrance in research, and Perutz first came up with the Multiple Isomorphous Replacement (MIR) method to resolve this problem. He worked with John Kendrew to solve this problem using isomorphous heavy atom derivatives. This method, along with X-ray diffraction methods, provides a new perspective on protein structure. The next achievement in the field was in 1980s when Williamson and his team provided the schematic representation of the first solution structure using Nuclear Magnetic Resonance (NMR) methods. The chapter states that crystallographers and NMR scientists have published most of their research in the form of diagrams. It stresses the importance of the “all proteins are created equal” principle. The chapter further points out that the content of the book focuses on the crystallographic and multidimensional NMR studies.
953 citations
TL;DR: The structure of Candida antarctica lipase B shows that the enzyme has a Ser-His-Asp catalytic triad in its active site, which accounts for the substrate specificity and high degree of stereospecificity of this lipase.
914 citations
TL;DR: In this article, the structure of β-Lg lattice Z at 3.0 A resolution by multiple isomorphous replacement and have partially refined it (R factor=24.8%).
705 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2022 | 1 |
| 2021 | 1 |
| 2015 | 1 |
| 2013 | 1 |
| 2010 | 2 |
| 2009 | 1 |