Protein Structures, Interactions and Function from Evolutionary Couplings

Author(s):  
Thomas A. Hopf ◽  
Debora S. Marks
Author(s):  
Mark Lorch

This chapter examines proteins, the dominant proportion of cellular machinery, and the relationship between protein structure and function. The multitude of biological processes needed to keep cells functioning are managed in the organism or cell by a massive cohort of proteins, together known as the proteome. The twenty amino acids that make up the bulk of proteins produce the vast array of protein structures. However, amino acids alone do not provide quite enough chemical variety to complete all of the biochemical activity of a cell, so the chapter also explores post-translation modifications. It finishes by looking as some dynamic aspects of proteins, including enzyme kinetics and the protein folding problem.


2020 ◽  
Vol 7 (8) ◽  
pp. 1410-1412
Author(s):  
Weijie Zhao ◽  
Chu Wang

Abstract Search ‘de novo protein design’ on Google and you will find the name David Baker in all results of the first page. Professor David Baker at the University of Washington and other scientists are opening up a new world of fantastic proteins. Protein is the direct executor of most biological functions and its structure and function are fully determined by its primary sequence. Baker's group developed the Rosetta software suite that enabled the computational prediction and design of protein structures. Being able to design proteins from scratch means being able to design executors for diverse purposes and benefit society in multiple ways. Recently, NSR interviewed Prof. Baker on this fast-developing field and his personal experiences.


2014 ◽  
Vol 10 (4) ◽  
Author(s):  
Jaume Bonet ◽  
Andras Fiser ◽  
Baldo Oliva ◽  
Narcis Fernandez-Fuentes

AbstractProtein structures are made up of periodic and aperiodic structural elements (i.e., α-helices, β-strands and loops). Despite the apparent lack of regular structure, loops have specific conformations and play a central role in the folding, dynamics, and function of proteins. In this article, we reviewed our previous works in the study of protein loops as local supersecondary structural motifs or Smotifs. We reexamined our works about the structural classification of loops (ArchDB) and its application to loop structure prediction (ArchPRED), including the assessment of the limits of knowledge-based loop structure prediction methods. We finalized this article by focusing on the modular nature of proteins and how the concept of Smotifs provides a convenient and practical approach to decompose proteins into strings of concatenated Smotifs and how can this be used in computational protein design and protein structure prediction.


2014 ◽  
Vol 70 (a1) ◽  
pp. C1603-C1603
Author(s):  
Vijay Reddy ◽  
Glen Nemerow

Human adenoviruses (HAdVs) are large (~150nm in diameter, 150MDa) nonenveloped double-stranded DNA (dsDNA) viruses that cause respiratory, ocular, and enteric diseases. The capsid shell of adenovirus (Ad) comprises multiple copies of three major capsid proteins (MCP: hexon, penton base and fiber) and four minor/cement proteins (IIIa, VI, VIII and IX) that are organized with pseudo T=25 icosahedral symmetry. In addition, six other proteins (V, VII, μ, IVa2, terminal protein and protease) are encapsidated along with the 36Kb dsDNA genome inside the capsid. The crystal structures of all three MCPs are known and so is their organization in the capsid from prior X-ray crystallography and cryoEM analyses. However structures and locations of various cement proteins are of considerable debate. We have determined and refined the structure of an entire human adenovirus employing X-ray crystallpgraphic methods at 3.8Å resolution. Adenovirus cement proteins play crucial roles in virion assembly, disassembly, cell entry and infection. Based on the refined crystal structure of adenovirus, we have determined the structure of the cement protein VI, a key membrane-lytic molecule and its associations with proteins V and VIII, which together glue peripentonal hexons beneath vertex region and connect them to rest of the capsid. Following virion maturation, the cleaved N-terminal pro-peptide of VI is observed deep in the peripentonal hexon cavity, detached from the membrane-lytic domain. Furthermore, we have significantly revised the recent cryoEM models for proteins IIIa and IX and both are located on the capsid exterior. Together, the cement proteins exclusively stabilize the hexon shell, thus rendering penton vertices the weakest links of the adenovirus capsid. Adenovirus cement protein structures reveal the molecular basis of the maturation cleavage of VI that is needed for endosome rupture and delivery of the virion into cytoplasm.


2014 ◽  
Vol 13 (06) ◽  
pp. 1450053 ◽  
Author(s):  
Meng Zhan ◽  
Suhong Li ◽  
Fan Li

Accurate prediction of the Debye–Waller temperature factor of proteins is of significant importance in the study of protein dynamics and function. This work explores the utility of wavelets for improving the performance of Gaussian network model (GNM). We propose two wavelet transformed Gaussian network models (wtGNM), namely a scale-one wtGNM and a scale-two wtGNM. Based on a set of 113 protein structures, it shows that the mean correlation with experimental results for the scale-one wtGNM is 0.714 and that for the scale-two wtGNM is 0.738. In contrast, the mean correlation for the original GNM is 0.594. Therefore, the wtGNM is a potential algorithm for improving the GNM prediction of protein B-factors.


2004 ◽  
Vol 1 (1) ◽  
pp. 80-89
Author(s):  
Guido Dieterich ◽  
Dirk W. Heinz ◽  
Joachim Reichelt

Abstract The 3D structures of biomacromolecules stored in the Protein Data Bank [1] were correlated with different external, biological information from public databases. We have matched the feature table of SWISS-PROT [2] entries as well InterPro [3] domains and function sites with the corresponding 3D-structures. OMIM [4] (Online Mendelian Inheritance in Man) records, containing information of genetic disorders, were extracted and linked to the structures. The exhaustive all-against-all 3D structure comparison of protein structures stored in DALI [5] was condensed into single files for each PDB entry. Results are stored in XML format facilitating its incorporation into related software. The resulting annotation of the protein structures allows functional sites to be identified upon visualization.


2014 ◽  
Vol 111 (10) ◽  
pp. 3865-3870 ◽  
Author(s):  
Brian C. Monk ◽  
Thomas M. Tomasiak ◽  
Mikhail V. Keniya ◽  
Franziska U. Huschmann ◽  
Joel D. A. Tyndall ◽  
...  

Bitopic integral membrane proteins with a single transmembrane helix play diverse roles in catalysis, cell signaling, and morphogenesis. Complete monospanning protein structures are needed to show how interaction between the transmembrane helix and catalytic domain might influence association with the membrane and function. We report crystal structures of full-length Saccharomyces cerevisiae lanosterol 14α-demethylase, a membrane monospanning cytochrome P450 of the CYP51 family that catalyzes the first postcyclization step in ergosterol biosynthesis and is inhibited by triazole drugs. The structures reveal a well-ordered N-terminal amphipathic helix preceding a putative transmembrane helix that would constrain the catalytic domain orientation to lie partly in the lipid bilayer. The structures locate the substrate lanosterol, identify putative substrate and product channels, and reveal constrained interactions with triazole antifungal drugs that are important for drug design and understanding drug resistance.


2002 ◽  
Vol 42 (5) ◽  
pp. 224-229
Author(s):  
Ken NISHIKAWA

2019 ◽  
Vol 5 (8) ◽  
pp. eaax4621 ◽  
Author(s):  
Hongyi Xu ◽  
Hugo Lebrette ◽  
Max T. B. Clabbers ◽  
Jingjing Zhao ◽  
Julia J. Griese ◽  
...  

Microcrystal electron diffraction (MicroED) has recently shown potential for structural biology. It enables the study of biomolecules from micrometer-sized 3D crystals that are too small to be studied by conventional x-ray crystallography. However, to date, MicroED has only been applied to redetermine protein structures that had already been solved previously by x-ray diffraction. Here, we present the first new protein structure—an R2lox enzyme—solved using MicroED. The structure was phased by molecular replacement using a search model of 35% sequence identity. The resulting electrostatic scattering potential map at 3.0-Å resolution was of sufficient quality to allow accurate model building and refinement. The dinuclear metal cofactor could be located in the map and was modeled as a heterodinuclear Mn/Fe center based on previous studies. Our results demonstrate that MicroED has the potential to become a widely applicable tool for revealing novel insights into protein structure and function.


1978 ◽  
Vol 33 (1-2) ◽  
pp. 96-104 ◽  
Author(s):  
P. L. Schell

Abstract 1) DNA-protein complexes are supposed to be original constituents of the membrane of Ehrlich ascites tum or cells. These complexes can be attacked at the surface of viable cells by DNase or protease. The DNA is partially embedded in protein structures.2) The net charge of this complex is of major importance for the RNA uptake capacity of the cells. Negatively charged DNA which is situated at the surface hinders RNA uptake. This is the explanation for the stimulation of RNA uptake by DNase or the decrease in RNA uptake after protease treatment.3) Upon treatment of DNA-dcficient complexes with homologous or heterologous DNA the original RNA uptake capacity of the cells is restored but the original conformation of the complex cannot be regained.4) The DNase action on the complex is tem perature dependent in a sigmoidal fashion. It is m arkedly slowed down at tem peratures below 12 °C. This implies that structural dianges in the complex occur at this transition tem perature which make surface DNA susceptible to DNase. This effect can only be observed in original structures but not in reconstituted ones.5) Polyanion treatment of the cells [poly (L-lysine) ] which increases their RNA uptake capacity, most probably does not interact with the DNA-protein complex. Poly (L-lysine) appears to act at other m em brane sites.6) The DNA-protein complex has been investigated entirely in situ , i. e. situated in the membrane of viable cells.


Sign in / Sign up

Export Citation Format

Share Document