https://zenodo.org/record/1258475/files/article.pdf

Electron transfers in chemistry and biology

Self-Assembly of Discrete Cyclic Nanostructures Mediated by Transition Metals

Publisher Summary This chapter investigates the anatomy and taxonomy of protein structures. A protein is a polypeptide chain made up of amino acid residues linked together in a definite sequence. Amino acids are “handed,” and naturally occurring proteins contain only L-amino acids. A simple mnemonic for that purpose is the “corncrib.” The sequence of side chains determines all that is unique about a particular protein, including its biological function and its specific three-dimensional structure. The major possible routes to knowledge of three-dimensional protein structure are prediction from the amino acid sequence and analysis of spectroscopic measurements such as circular dichroism, laser Raman spectroscopy, and nuclear magnetic resonance. The analysis and discussion of protein structure is based on the results of three-dimensional X-ray crystallography of globular proteins. The basic elements of protein structures are discussed. The most useful level at which protein structures are to be categorized is the domain, as there are many cases of multiple-domain proteins in which each separate domain resembles other entire smaller proteins. The simplest type of stable protein structure consists of polypeptide backbone wrapped more or less uniformly around the outside of a single hydrophobic core. The outline of the taxonomy is also provided in the chapter.

The anatomy and taxonomy of protein structure.

A human IgGI antibody has been reshaped for serotherapy in humans by introducing the six hypervariable regions from the heavy- and light-chain variable domains of a rat antibody directed against human lymphocytes. The reshaped human antibody is as effective as the rat antibody in complement and is more effective in cell-mediated lysis of human lymphocytes.

Reshaping human antibodies for therapy.

Photosynthesis uses light energy to drive the oxidation of water at an oxygen-evolving catalytic site within photosystem II (PSII). We report the structure of PSII of the cyanobacterium Thermosynechococcus elongatus at 3.5 angstrom resolution. We have assigned most of the amino acid residues of this 650-kilodalton dimeric multisubunit complex and refined the structure to reveal its molecular architecture. Consequently, we are able to describe details of the binding sites for cofactors and propose a structure of the oxygen-evolving center (OEC). The data strongly suggest that the OEC contains a cubane-like Mn 3 CaO 4 cluster linked to a fourth Mn by a mono-μ-oxo bridge. The details of the surrounding coordination sphere of the metal cluster and the implications for a possible oxygen-evolving mechanism are discussed.

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Architecture of the Photosynthetic Oxygen-Evolving Center

The analysis of a monoclinic crystal modification of l-asparaginase from Escherichia coli supports the chemical and physio-chemical evidence for a tetrameric subunit structure.



The pseudo-symmetries occurring in the crystal structure provide evidence that the molecules lie on positions with approximate point symmetry 222.

https://febs.onlinelibrary.wiley.com/doi/epdf/10.1111/j.1432-1033.1971.tb01410.x

Crystallographic evidence for the tetrameric subunit structure of L-asparaginase from Escherichia coli.

The structure of a χ-type Bence-Jones protein variable fragment Au has been determined by molecular replacement methods using the known structure of an other Bence-Jones variable fragment Rei (Epp et al., Eur. J. Biochem. 45, 513 (1974)). The crystallographic R factor is 0.31 for about 4000 significantly measured reflections between 6.8 to 2.5 a. The Au protein forms a dimer across a crystallographic two fold axis. The spatial relationship of the two monomers, the conformation of the backbones and of the internal residues is extremely similar to that found in Rei.

The structure determination of the variable portion of the Bence-Jones protein Au.

Solution of the phase problem in the X-ray diffraction method for proteins with the nuclear magnetic resonance solution structure as initial model: Patterson search and refinement for the α-amylase inhibitor tendamistat

Die Tertiarstrukturen des Insektenhamoglobins Erythrocruorin und der Vertebraten-Hamoglobine sind sehr ahnlich. Eine Ausnahme bildet ein Knick in der Helix H.

Otto Epp

Papers

Crystallographic evidence for the tetrameric subunit structure of L-asparaginase from Escherichia coli.

The structure determination of the variable portion of the Bence-Jones protein Au.

Solution of the phase problem in the X-ray diffraction method for proteins with the nuclear magnetic resonance solution structure as initial model: Patterson search and refinement for the α-amylase inhibitor tendamistat

Aufklärung der Molekülstruktur des Insektenhämoglobins

Elucidation of the molecular structure of insect hemoglobin