The role of post-translational modification in the photoregulation of Fe-type nitrile hydrataseElectronic supplementary information (ESI) available: Selected structural parameters of the experimentally observed NHase active site and DFT-optimised models 1 and 2, and graphical MO representations of the calculated INDO/S spectroscopic transitions for the models discussed. See http://www.rsc.org/suppdata/cc/b2/b207027h/

2002 ◽  
pp. 2386-2387 ◽  
Author(s):  
Shannon N. Greene ◽  
Christopher H. Chang ◽  
Nigel G. J. Richards
Keyword(s):  
Active Site ◽  
Structural Parameters ◽  
Supplementary Information ◽  
Post Translational Modification

scholarly journals Structures of prokaryotic ubiquitin-like protein Pup in complex with depupylase Dop reveal the mechanism of catalytic phosphate formation

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Hengjun Cui ◽  
Andreas U. Müller ◽  
Marc Leibundgut ◽  
Jiawen Tian ◽  
Nenad Ban ◽  
...  
Keyword(s):  
High Resolution ◽  
Sequence Homology ◽  
Active Site ◽  
Bound States ◽  
Biochemical Analysis ◽  
Atp Hydrolysis ◽  
Reaction Pathway ◽  
Post Translational Modification ◽  
Functional States

AbstractPupylation is the post-translational modification of lysine side chains with prokaryotic ubiquitin-like protein (Pup) that targets proteins for proteasomal degradation in mycobacteria and other members of Actinobacteria. Pup ligase PafA and depupylase Dop are the two enzymes acting in this pathway. Although they share close structural and sequence homology indicative of a common evolutionary origin, they catalyze opposing reactions. Here, we report a series of high-resolution crystal structures of Dop in different functional states along the reaction pathway, including Pup-bound states in distinct conformations. In combination with biochemical analysis, the structures explain the role of the C-terminal residue of Pup in ATP hydrolysis, the process that generates the catalytic phosphate in the active site, and suggest a role for the Dop-loop as an allosteric sensor for Pup-binding and ATP cleavage.

scholarly journals Trp–His covalent adduct in bilirubin oxidase is crucial for effective bilirubin binding but has a minor role in electron transfer

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Tomáš Kovaľ ◽  
Leona Švecová ◽  
Lars H. Østergaard ◽  
Tereza Skalova ◽  
Jarmila Dušková ◽  
...  
Keyword(s):  
Electron Transfer ◽  
Active Site ◽  
Substrate Binding ◽  
Minor Role ◽  
Post Translational Modification ◽  
Unique Type ◽  
Bilirubin Oxidase ◽  
Bilirubin Binding ◽  
A Minor

Abstract Unlike any protein studied so far, the active site of bilirubin oxidase from Myrothecium verrucaria contains a unique type of covalent link between tryptophan and histidine side chains. The role of this post-translational modification in substrate binding and oxidation is not sufficiently understood. Our structural and mutational studies provide evidence that this Trp396–His398 adduct modifies T1 copper coordination and is an important part of the substrate binding and oxidation site. The presence of the adduct is crucial for oxidation of substituted phenols and it substantially influences the rate of oxidation of bilirubin. Additionally, we bring the first structure of bilirubin oxidase in complex with one of its products, ferricyanide ion, interacting with the modified tryptophan side chain, Arg356 and the active site-forming loop 393-398. The results imply that structurally and chemically distinct types of substrates, including bilirubin, utilize the Trp–His adduct mainly for binding and to a smaller extent for electron transfer.

Pathogenesis of Age-related Cataract: a systematic review of proteomic studies

2020 ◽  
Vol 17 ◽  
Author(s):  
Christina Karakosta ◽  
Argyrios Tzamalis ◽  
Michalis Aivaliotis ◽  
Ioannis Tsinopoulos
Keyword(s):  
Systematic Review ◽  
Oxidant Stress ◽  
Critical Role ◽  
Human Lens ◽  
Nuclear Cataract ◽  
Cataract Formation ◽  
Post Translational Modification ◽  
Ability To Act ◽  
Age Related

Background/Objective:: The aim of this systematic review is to identify all the available data on human lens proteomics with a critical role to age-related cataract formation in order to elucidate the physiopathology of the aging lens. Materials and Methods:: We searched on Medline and Cochrane databases. The search generated 328 manuscripts. We included nine original proteomic studies that investigated human cataractous lenses. Results:: Deamidation was the major age-related post-translational modification. There was a significant increase in the amount of αA-crystallin D-isoAsp58 present at all ages, while an increase in the extent of Trp oxidation was apparent in cataract lenses when compared to aged normal lenses. During aging, enzymes with oxidized cysteine at critical sites included GAPDH, glutathione synthase, aldehyde dehydrogenase, sorbitol dehydrogenase, and PARK7. Conclusion:: D-isoAsp in αA crystallin could be associated with the development of age-related cataract in human, by contributing to the denaturation of a crystallin, and decreasing its ability to act as a chaperone. Oxidation of Trp may be associated with nuclear cataract formation in human, while the role of oxidant stress in age-related cataract formation is dominant.

scholarly journals System-wide identification and prioritization of enzyme substrates by thermal analysis

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Amir Ata Saei ◽  
Christian M. Beusch ◽  
Pierre Sabatier ◽  
Juan Astorga Wells ◽  
Hassan Gharibi ◽  
...  
Keyword(s):  
Thermal Analysis ◽  
Thioredoxin Reductase ◽  
Structural Level ◽  
Post Translational Modification ◽  
Post Translational Modifications ◽  
Enzyme Substrate ◽  
Thioredoxin Reductase 1 ◽  
Enzyme Substrates ◽  
Substrate Proteins

AbstractDespite the immense importance of enzyme–substrate reactions, there is a lack of general and unbiased tools for identifying and prioritizing substrate proteins that are modified by the enzyme on the structural level. Here we describe a high-throughput unbiased proteomics method called System-wide Identification and prioritization of Enzyme Substrates by Thermal Analysis (SIESTA). The approach assumes that the enzymatic post-translational modification of substrate proteins is likely to change their thermal stability. In our proof-of-concept studies, SIESTA successfully identifies several known and novel substrate candidates for selenoprotein thioredoxin reductase 1, protein kinase B (AKT1) and poly-(ADP-ribose) polymerase-10 systems. Wider application of SIESTA can enhance our understanding of the role of enzymes in homeostasis and disease, opening opportunities to investigate the effect of post-translational modifications on signal transduction and facilitate drug discovery.

scholarly journals Biomechanical Properties of Cancer Cells

Cells ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 887
Author(s):  
Gaël Runel ◽  
Noémie Lopez-Ramirez ◽  
Julien Chlasta ◽  
Ingrid Masse
Keyword(s):  
Cancer Cells ◽  
Cancer Diagnosis ◽  
Crucial Role ◽  
Biomechanical Properties ◽  
Supplementary Information ◽  
Cancer Cell Growth ◽  
Diagnosis And Prognosis ◽  
Surrounding Environment ◽  
Surrounding Extracellular Matrix

Since the crucial role of the microenvironment has been highlighted, many studies have been focused on the role of biomechanics in cancer cell growth and the invasion of the surrounding environment. Despite the search in recent years for molecular biomarkers to try to classify and stratify cancers, much effort needs to be made to take account of morphological and nanomechanical parameters that could provide supplementary information concerning tissue complexity adaptation during cancer development. The biomechanical properties of cancer cells and their surrounding extracellular matrix have actually been proposed as promising biomarkers for cancer diagnosis and prognosis. The present review first describes the main methods used to study the mechanical properties of cancer cells. Then, we address the nanomechanical description of cultured cancer cells and the crucial role of the cytoskeleton for biomechanics linked with cell morphology. Finally, we depict how studying interaction of tumor cells with their surrounding microenvironment is crucial to integrating biomechanical properties in our understanding of tumor growth and local invasion.

scholarly journals Role of Host-Mediated Post-Translational Modifications (PTMs) in RNA Virus Pathogenesis

2020 ◽  
Vol 22 (1) ◽  
pp. 323
Author(s):  
Ramesh Kumar ◽  
Divya Mehta ◽  
Nimisha Mishra ◽  
Debasis Nayak ◽  
Sujatha Sunil
Keyword(s):  
Rna Virus ◽  
Viral Proteins ◽  
Post Translational Modification ◽  
Host Proteins ◽  
Viral Protein Synthesis ◽  
Post Translational Modifications ◽  
Small Proteins ◽  
Cellular Machinery ◽  
Chemical Groups

Being opportunistic intracellular pathogens, viruses are dependent on the host for their replication. They hijack host cellular machinery for their replication and survival by targeting crucial cellular physiological pathways, including transcription, translation, immune pathways, and apoptosis. Immediately after translation, the host and viral proteins undergo a process called post-translational modification (PTM). PTMs of proteins involves the attachment of small proteins, carbohydrates/lipids, or chemical groups to the proteins and are crucial for the proteins’ functioning. During viral infection, host proteins utilize PTMs to control the virus replication, using strategies like activating immune response pathways, inhibiting viral protein synthesis, and ultimately eliminating the virus from the host. PTM of viral proteins increases solubility, enhances antigenicity and virulence properties. However, RNA viruses are devoid of enzymes capable of introducing PTMs to their proteins. Hence, they utilize the host PTM machinery to promote their survival. Proteins from viruses belonging to the family: Togaviridae, Flaviviridae, Retroviridae, and Coronaviridae such as chikungunya, dengue, zika, HIV, and coronavirus are a few that are well-known to be modified. This review discusses various host and virus-mediated PTMs that play a role in the outcome during the infection.

The Role of Understanding on Architectural Beauty: Evidence From the Impact of Semantic Description on the Aesthetic Evaluation of Architecture

2021 ◽  
pp. 003329412110021
Author(s):  
Sizhe Liu ◽  
Wei Zhang ◽  
Xianyou He ◽  
Xiaoxiang Tang ◽  
Shuxian Lai ◽  
...  
Keyword(s):  
Aesthetic Experience ◽  
Supplementary Information ◽  
Aesthetic Evaluation ◽  
Abstract Description ◽  
Social Meanings ◽  
Different Types ◽  
Appearance Design ◽  
The Aesthetic ◽  
The Impact

There is evidence that greater aesthetic experience can be linked to artworks when their corresponding meanings can be successfully inferred and understood. Modern cultural-expo architecture can be considered a form of artistic creation and design, and the corresponding design philosophy may be derived from representational objects or abstract social meanings. The present study investigates whether cultural-expo architecture with an easy-to-understand architectural appearance design is perceived as more beautiful and how architectural photographs and different types of descriptions of architectural appearance designs interact and produce higher aesthetic evaluations. The results showed an obvious aesthetic preference for cultural-expo architecture with an easy-to-understand architectural appearance design (Experiment 1). Moreover, we found that the aesthetic rating score of architectural photographs accompanied by an abstract description was significantly higher than that of those accompanied by a representational description only under the difficult-to-understand design condition (Experiment 2). The results indicated that people preferred cultural-expo architecture with an easy-to-understand architectural appearance design due to a greater understanding of the design, providing further evidence that abstract descriptions can provide supplementary information and explanation to enhance the sense of beauty of abstract cultural-expo architecture.

Exploring the Role of the Central Carbide of the Nitrogenase Active-Site FeMo-cofactor through Targeted 13C Labeling and ENDOR Spectroscopy

2021 ◽  
Author(s):  
Ana Pérez-González ◽  
Zhi-Yong Yang ◽  
Dmitriy A. Lukoyanov ◽  
Dennis R. Dean ◽  
Lance C. Seefeldt ◽  
...  
Keyword(s):  
Active Site ◽  
13C Labeling ◽  
Endor Spectroscopy ◽  
Femo Cofactor
Sign in / Sign up

Export Citation Format

Share Document