Serine and Cysteine π-Interactions in Nature: A Comparison of the Frequency, Structure, and Stability of Contacts Involving Oxygen and Sulfur

2015 ◽  
Vol 68 (3) ◽  
pp. 385 ◽  
Author(s):  
Hanzala B. Hussain ◽  
Katie A. Wilson ◽  
Stacey D. Wetmore
Keyword(s):  
Amino Acids ◽  
High Resolution ◽  
Protein Stability ◽  
Crystal Structures ◽  
Protein Complexes ◽  
Aromatic Amino Acids ◽  
Biological Macromolecules ◽  
Great Stability ◽  
Π Interactions ◽  
And Function

Despite many DNA–protein π-interactions in high-resolution crystal structures, only four X–H···π or X···π interactions were found between serine (Ser) or cysteine (Cys) and DNA nucleobase π-systems in over 100 DNA–protein complexes (where X = O for Ser and X = S for Cys). Nevertheless, 126 non-covalent contacts occur between Ser or Cys and the aromatic amino acids in many binding arrangements within proteins. Furthermore, Ser and Cys protein–protein π-interactions occur with similar frequencies and strengths. Most importantly, due to the great stability that can be provided to biological macromolecules (up to –20 kJ mol–1 for neutral π-systems or –40 kJ mol–1 for cationic π-systems), Ser and Cys π-interactions should be considered when analyzing protein stability and function.

Crystal Structures of Fragments D and Double-D from Fibrinogen and Fibrin

1999 ◽  
Vol 82 (08) ◽  
pp. 271-276 ◽  
Author(s):  
Glen Spraggon ◽  
Stephen Everse ◽  
Russell Doolittle
Keyword(s):  
Electron Microscopy ◽  
High Resolution ◽  
Crystal Structures ◽  
Structure And Function ◽  
X Ray ◽  
Long Period ◽  
And Function

IntroductionAfter a long period of anticipation,1 the last two years have witnessed the first high-resolution x-ray structures of fragments from fibrinogen and fibrin.2-7 The results confirmed many aspects of fibrinogen structure and function that had previously been inferred from electron microscopy and biochemistry and revealed some unexpected features. Several matters have remained stubbornly unsettled, however, and much more work remains to be done. Here, we review several of the most significant findings that have accompanied the new x-ray structures and discuss some of the problems of the fibrinogen-fibrin conversion that remain unresolved. * Abbreviations: GPR—Gly-Pro-Arg-derivatives; GPRPam—Gly-Pro-Arg-Pro-amide; GHRPam—Gly-His-Arg-Pro-amide

Three-dimensional crystallization of membrane proteins

1988 ◽  
Vol 21 (4) ◽  
pp. 429-477 ◽  
Author(s):  
W. Kühlbrandt
Keyword(s):  
High Resolution ◽  
Membrane Proteins ◽  
Membrane Protein ◽  
Protein Complexes ◽  
Three Dimensional ◽  
Biological Macromolecules ◽  
X Ray ◽  
X Ray Crystallography ◽  
Membrane Protein Complexes ◽  
Essential Prerequisite

As recently as 10 years ago, the prospect of solving the structure of any membrane protein by X-ray crystallography seemed remote. Since then, the threedimensional (3-D) structures of two membrane protein complexes, the bacterial photosynthetic reaction centres of Rhodopseudomonas viridis (Deisenhofer et al. 1984, 1985) and of Rhodobacter sphaeroides (Allen et al. 1986, 1987 a, 6; Chang et al. 1986) have been determined at high resolution. This astonishing progress would not have been possible without the pioneering work of Michel and Garavito who first succeeded in growing 3-D crystals of the membrane proteins bacteriorhodopsin (Michel & Oesterhelt, 1980) and matrix porin (Garavito & Rosenbusch, 1980). X-ray crystallography is still the only routine method for determining the 3-D structures of biological macromolecules at high resolution and well-ordered 3-D crystals of sufficient size are the essential prerequisite.

scholarly journals Formaldehyde Reacts with Amino Acids and Peptides with a Potential Role in Acute Methanol Intoxication

2020 ◽  
Vol 44 (8) ◽  
pp. 880-885 ◽  
Author(s):  
David Sýkora ◽  
Jindřich Jindřich ◽  
Vladimír Král ◽  
Milan Jakubek ◽  
Ameneh Tatar ◽  
...  
Keyword(s):  
Amino Acids ◽  
High Resolution ◽  
High Resolution Mass Spectrometry ◽  
Cytotoxic T Lymphocyte ◽  
Mass Shift ◽  
Biologically Relevant ◽  
Igg1 Monoclonal Antibody ◽  
Human Igg1 ◽  
And Function

Abstract Methanol, an aliphatic alcohol widely used in the industry, causes acute and chronic intoxications associated with severe long-term health damage, including permanent visual impairment, brain damage, mainly necrosis of the basal ganglia and high mortality due to cancer. However, the role of formaldehyde, an intermediate metabolite of methanol oxidation, in methanol toxicity remains unclear. Thus, we studied the reactivity of several amino acids and peptides in the presence of formaldehyde by identifying products by direct infusion electrospray high-resolution mass spectrometry (MS) and matrix-assisted laser desorption-ionization MS. Cysteine, homocysteine and two peptides, CG and CGAG, provided cyclic products with a +12 amu mass shift with respect to the original compounds. The proposed structures of the products were confirmed by high-resolution tandem MS. Moreover, the formation of the products with +12 amu mass shift was also shown for two biologically relevant peptides, fragments of ipilimumab, which is a human IgG1 monoclonal antibody against cytotoxic T-lymphocyte-associated protein 4. Overall, our experimental results indicate that formaldehyde reacts with some amino acids and peptides, yielding covalently modified structures. Such chemical modifications may induce undesirable changes in the properties and function of vital biomolecules (e.g., hormones, enzymes) and consequently pathogenesis.

Combined DFT and MD simulation studies of protein stability on imidazolium–water (ImH+Wn) clusters with aromatic amino acids

2020 ◽  
Vol 44 (41) ◽  
pp. 17912-17923
Author(s):  
Kandhan Palanisamy ◽  
Muthuramalingam Prakash ◽  
Varatharaj Rajapandian
Keyword(s):  
Amino Acids ◽  
Protein Stability ◽  
Md Simulation ◽  
Protein Denaturation ◽  
Aromatic Amino Acids ◽  
Simulation Studies ◽  
Π Stacking ◽  
Hydrated Clusters

The hydrated clusters of protonated imidazole (ImH+) can induce protein denaturation through various kinds of monovalent interactions such as cation···π (stacking), N–H⋯π (T-shaped) and water-mediated O–H⋯O H-bonds.

Frank William Ernest Gibson 1923 - 2008

2010 ◽  
Vol 21 (1) ◽  
pp. 55 ◽  
Author(s):  
A. J. Pittard ◽  
G. B. Cox
Keyword(s):  
Escherichia Coli ◽  
Amino Acids ◽  
Genetic Analysis ◽  
Aromatic Compounds ◽  
Aromatic Amino Acids ◽  
Atp Synthesis ◽  
Structure And Function ◽  
Innovative Model ◽  
Distinguished Research ◽  
And Function

Frank Gibson died in Canberra on 11 July 2008. Frank was a highly distinguished research scientist who will be remembered for his pioneering studies in identifying the branch-point compound in the pathway of biosynthesis of a large number of important aromatic compounds followed by a detailed biochemical and genetic analysis of many of the pathways leading to the aromatic amino acids and the so-called aromatic vitamins. Studies on ubiquinone synthesis and function led to an examination of oxidative phosphorylation and the structure and function of the F1F0-ATPase in the bacterium Escherichia coli. This work resulted in the formulation of a highly innovative model, involving rotating subunits of the F0 segment within the membrane and offering an explanation for the mechanism linking proton flow and ATP synthesis.

On the interaction between the imidazolium cation and aromatic amino acids. A computational study

2015 ◽  
Vol 13 (29) ◽  
pp. 7961-7972 ◽  
Author(s):  
Ana A. Rodríguez-Sanz ◽  
Enrique M. Cabaleiro-Lago ◽  
Jesús Rodríguez-Otero
Keyword(s):  
Amino Acids ◽  
Computational Study ◽  
Aromatic Amino Acids ◽  
Imidazolium Cation ◽  
Π Interactions

Phe, Tyr and Trp form parallel complexes with cation⋯π interactions. His complexes are the strongest, but without making contact with the aromatic cloud.

scholarly journals The molecular appearance of native TRPM7 channel complexes identified by high-resolution proteomics

2021 ◽  
Author(s):  
Astrid Kollewe ◽  
Vladimir Chubanov ◽  
Fong Tsuen Tseung ◽  
Alexander Haupt ◽  
Catrin Swantje M&uumlller ◽  
...  
Keyword(s):  
High Resolution ◽  
Transient Receptor Potential ◽  
Protein Complexes ◽  
Divalent Cations ◽  
Affinity Purification ◽  
Receptor Potential ◽  
Metal Transporter ◽  
Transient Receptor Potential Melastatin ◽  
Transient Receptor ◽  
And Function

The transient receptor potential melastatin-subfamily member 7 (TRPM7) is a ubiquitously expressed membrane protein consisting of ion channel and protein kinase domains. TRPM7 plays a fundamental role in the cellular uptake of divalent cations such as Zn2+, Mg2+ and Ca2+, and thus shapes cellular excitability, plasticity and metabolic activity. The molecular appearance and operation of TRPM7 channel complexes in native tissues have remained unresolved. Here, we investigated the subunit composition of endogenous TRPM7 channels in rodent brain by multi-epitope affinity purification and high-resolution quantitative MS analysis. We found that native TRPM7 channels are high molecular-weight multi-protein complexes that contain the putative metal transporter proteins CNNM1-4 and a small G-protein ARL15. Heterologous reconstitution experiments confirmed the formation of TRPM7/CNNM/ARL15 ternary complexes and indicated that ARL15 effectively and specifically impacts TRPM7 channel activity. These results open up new avenues towards a mechanistic understanding of the cellular regulation and function of TRPM7 channels.

scholarly journals Evaluating Unexpectedly Short Non-covalent Distances in X-ray Crystal Structures of Proteins with Electronic Structure Analysis

2019 ◽  
Author(s):  
Helena W. Qi ◽  
Heather Kulik
Keyword(s):  
Amino Acids ◽  
High Resolution ◽  
Crystal Structures ◽  
Close Contact ◽  
Protein Structures ◽  
Protein Crystal ◽  
X Ray ◽  
High Quality Protein ◽  
Van Der Waals Radii ◽  
Close Contacts

<div><div><div><p>We investigate unexpectedly short non-covalent distances (< 85% of the sum of van der Waals radii) in atomically resolved X-ray crystal structures of proteins. We curate over 13,000 high quality protein crystal structures and an ultra-high resolution (1.2 Å or better) subset containing > 1,000 structures. Although our non-covalent distance criterion excludes standard hydrogen bonds known to be essential in protein stability, we observe over 82,000 close contacts in the curated protein structures. Analysis of the frequency of amino acids participating in these interactions demonstrates some expected trends (i.e., enrichment of charged Lys, Arg, Asp, and Glu) but also reveals unexpected enhancement of Tyr in such interactions. Nearly all amino acids are observed to form at least one close contact with all other amino acids, and most interactions are preserved in the much smaller ultra high-resolution subset. We quantum-mechanically characterize the interaction energetics of a subset of > 6,000 close contacts with symmetry adapted perturbation theory to enable decomposition of interactions. We observe the majority of close contacts to be favorable. The shortest favorable non-covalent distances are under 2.2 Å and are very repulsive when characterized with classical force fields. This analysis reveals stabilization by a combination of electrostatic and charge transfer effects between hydrophobic (i.e., Val, Ile, Leu) amino acids and charged Asp or Glu. We also observe a unique hydrogen bonding configuration between Tyr and Asn/Gln involving both residues acting simultaneously as hydrogen bond donors and acceptors. This work confirms the importance of first-principles simulation in explaining unexpected geometries in protein crystal structures.</p></div></div></div>

scholarly journals Crystal structures of Aspergillus oryzae Rib2 deaminase: the functional mechanism involved in riboflavin biosynthesis

IUCrJ ◽  
2021 ◽  
Vol 8 (4) ◽  
Author(s):  
Sheng-Chia Chen ◽  
Li-Ci Ye ◽  
Te-Ming Yen ◽  
Ruei-Xin Zhu ◽  
Cheng-Yu Li ◽  
...  
Keyword(s):  
Enzyme Activity ◽  
High Resolution ◽  
Protein Stability ◽  
Crystal Structures ◽  
Aspergillus Oryzae ◽  
Terminal Segment ◽  
Riboflavin Biosynthesis ◽  
The Third ◽  
Complex Forms ◽  
Deaminase Domain

Riboflavin serves as the direct precursor of the FAD/FMN coenzymes and is biosynthesized in most prokaryotes, fungi and plants. Fungal Rib2 possesses a deaminase domain for deamination of pyrimidine in the third step of riboflavin biosynthesis. Here, four high-resolution crystal structures of a Rib2 deaminase from Aspergillus oryzae (AoRib2) are reported which display three distinct occluded, open and complex forms that are involved in substrate binding and catalysis. In addition to the deaminase domain, AoRib2 contains a unique C-terminal segment which is rich in charged residues. Deletion of this unique segment has no effect on either enzyme activity or protein stability. Nevertheless, the C-terminal αF helix preceding the segment plays a role in maintaining protein stability and activity. Unexpectedly, AoRib2 is the first mononucleotide deaminase found to exist as a monomer, perhaps due to the assistance of its unique longer loops (Lβ1–β2, LαB–β3 and LαC–β4). These results form the basis for a molecular understanding of riboflavin biosynthesis in fungi and might assist in the development of antibiotics.

ACMS: a database of alternate conformations found in the atoms of main and side chains of protein structures

2019 ◽  
Vol 52 (4) ◽  
pp. 910-913 ◽  
Author(s):  
R. Santhosh ◽  
P. Chandrasekaran ◽  
Daliah Michael ◽  
K. Rangachari ◽  
Namrata Bankoti ◽  
...  
Keyword(s):  
High Resolution ◽  
Knowledge Base ◽  
Crystal Structures ◽  
Protein Structures ◽  
Protein Molecule ◽  
Data Bank ◽  
Side Chain ◽  
Biological Macromolecules ◽  
Conformational Ensembles ◽  
User Friendly

Proteins are usually dynamic biological macromolecules, thereby exhibiting a large number of conformational ensembles which influence the association with their neighbours and interacting partners. Most of the side-chain atoms and a few main-chain atoms of the high-resolution crystal structures deposited in the Protein Data Bank adopt alternate conformations. This kind of conformational behaviour prompted the authors to explore the relationship, if any, between the alternate conformations and the function of the protein molecule. Thus, a knowledge base of the alternate conformations of the main- and side-chain atoms of protein structures has been developed. It provides a detailed description of the alternate conformations of various residues for more than 60 000 high-resolution crystal structures. The proposed knowledge base is very user friendly and has various flexible options. The knowledge base will be updated periodically and can be accessed at http://iris.physics.iisc.ac.in/acms.

Sign in / Sign up

Export Citation Format

Share Document