scholarly journals The htrA Gene Plays an Important role During Yersinia Pseudotuberculosis Growth at High Temperature

2020 ◽  
Author(s):  
Elena Escobar Garduño ◽  
Lucia Soto Urzua ◽  
Rogelio Rodriguez Sotres ◽  
Luis Javier Martinez Morales

Abstract htrA is a gene coding for the stress inducible HtrA protein, identified as a temperature stress response protein in several Gram positive and Gram negative bacteria. Growth rates at several temperatures (30ºC, 37ºC and 42ºC) were compared for Yersinia pseudotuberculosis YPIII wild strain and the isogenic mutant 1YPIII (htrA::Km), which was obtained by insertion of a kanamycin resistance cassette into the htrA gene.Y. pseudotuberculosis 1YPIII growth rates did not differ from the Y. pseudotuberculosis wild strain growth rates when cultivated at 30°C, which is consistent with a non-essential role for the HtrA protein at this temperature. However, 1YPIII mutant strain growth rate decreased by 18.73% at 37°C, and by 60.14% at 42°C, as compared to the Y. pseudotuberculosis YPIII wild strain growth rate. HtrA complementation in the strain 1YPIII/pAHTRA46 suppressed the differences in growth rates. Immunoblot analysis confirmed the absence of the HtrA protein in the 1YPIII mutant strain at any of the growth temperatures under analysis. In silico predictions were obtained for the three-dimensional structure of amino acid sequence belonging to HtrA from Y. pseudotuberculosis YPIII, Yersinia pestis CO92, using the protein data bank structure 1KY9:B from Escherichia coli, as template. The model's quality was found to be acceptable. Southern blot analysis shows a single htrA gene signal. These data indicate that the unique htrA gene in Y. pseudotuberculosis YPIII is required for the adaptive response of this species to high temperatures and although it is not a pathogenicity factor, it can be targeted by antibiotics.


2020 ◽  
Vol 5 (7) ◽  
Author(s):  
Lucas Paul ◽  
Celestin N. Mudogo ◽  
Kelvin M. Mtei ◽  
Revocatus L. Machunda ◽  
Fidele Ntie-Kang

AbstractCassava is a strategic crop, especially for developing countries. However, the presence of cyanogenic compounds in cassava products limits the proper nutrients utilization. Due to the poor availability of structure discovery and elucidation in the Protein Data Bank is limiting the full understanding of the enzyme, how to inhibit it and applications in different fields. There is a need to solve the three-dimensional structure (3-D) of linamarase from cassava. The structural elucidation will allow the development of a competitive inhibitor and various industrial applications of the enzyme. The goal of this review is to summarize and present the available 3-D modeling structure of linamarase enzyme using different computational strategies. This approach could help in determining the structure of linamarase and later guide the structure elucidation in silico and experimentally.



2019 ◽  
Vol 52 (6) ◽  
pp. 1422-1426
Author(s):  
Rajendran Santhosh ◽  
Namrata Bankoti ◽  
Adgonda Malgonnavar Padmashri ◽  
Daliah Michael ◽  
Jeyaraman Jeyakanthan ◽  
...  

Missing regions in protein crystal structures are those regions that cannot be resolved, mainly owing to poor electron density (if the three-dimensional structure was solved using X-ray crystallography). These missing regions are known to have high B factors and could represent loops with a possibility of being part of an active site of the protein molecule. Thus, they are likely to provide valuable information and play a crucial role in the design of inhibitors and drugs and in protein structure analysis. In view of this, an online database, Missing Regions in Polypeptide Chains (MRPC), has been developed which provides information about the missing regions in protein structures available in the Protein Data Bank. In addition, the new database has an option for users to obtain the above data for non-homologous protein structures (25 and 90%). A user-friendly graphical interface with various options has been incorporated, with a provision to view the three-dimensional structure of the protein along with the missing regions using JSmol. The MRPC database is updated regularly (currently once every three months) and can be accessed freely at the URL http://cluster.physics.iisc.ac.in/mrpc.



Author(s):  
Gabriel Jan Abrahams ◽  
Janet Newman

Crystallization is in many cases a critical step for solving the three-dimensional structure of a protein molecule. Determining which set of chemicals to use in the initial screen is typically agnostic of the protein under investigation; however, crystallization efficiency could potentially be improved if this were not the case. Previous work has assumed that sequence similarity may provide useful information about appropriate crystallization cocktails; however, the authors are not aware of any quantitative verification of this assumption. This research investigates whether, given current information, one can detect any correlation between sequence similarity and crystallization cocktails. BLAST was used to quantitate the similarity between protein sequences in the Protein Data Bank, and this was compared with three estimations of the chemical similarities of the respective crystallization cocktails. No correlation was detected between proteins of similar (but not identical) sequence and their crystallization cocktails, suggesting that methods of determining screens based on this assumption are unlikely to result in screens that are better than those currently in use.



Author(s):  
SANGEETA RANI ◽  
KAVITA GAHLOT ◽  
ARVIND KUMAR

Objective: The purpose of this study was to investigate the diabetic effect of phytocompounds isolated from Cressa cretica Linn. using spectroscopic analysis and molecular docking studies. Methods: Coarse powder of the whole plant of C. cretica was extracted with methanol, extracted part was subjected to silica column isolation, and two compounds: 2-Isopropyl-4-(1-methyl-dodeca-2,4-dienyloxy)-benzene-1,3,5-triol (Compound CN-01) and 11-Methyl-dodeca-2,4,6,8,10-pentenoic acid 2,3-dihydroxy-5-methyl-phenyl ester (Compound CN-02) were isolated in pure form. The three-dimensional structure of target protein was downloaded from PDB (www.rcsb.org) Protein Data Bank, Ligand file CN – 01 and CN – 02 were converted to MDL Molfile (V2000) format using ChemSketch 2017.2.1. These files could not be used directly in AutoDock 4.0 tools; thus, they were first converted to PDB files using an open babel tool. Results: Compounds were revealed through spectroscopic analysis and screened using AutoDock 4.0 tools. Docking study recommended that CN – 01 and CN – 02 an existing phytochemical from the plant of C. cretica had the highest fitness docking score and hence could be a potent antidiabetic drug. Conclusion: In this investigation, we docked the receptor (glycogen phosphorylase protein) holds a promising lead target formation against diabetes based on molecular docking analysis (minimum hydrogen bond length and maximum docked score). Thus, these compounds can be effectively used as drugs for treating diabetes which is predicted on the basis of docking scores.



Biologia ◽  
2014 ◽  
Vol 69 (3) ◽  
Author(s):  
Venkatesh Kumaresan ◽  
Prasanth Bhatt ◽  
Rajesh Palanisamy ◽  
Annie Gnanam ◽  
Mukesh Pasupuleti ◽  
...  

AbstractCathepsin L, a lysosomal endopeptidase, is a member of the peptidase C1 family (papain-like family) of cysteine proteinases that cleave peptide bonds of lysosomal proteins. In this study, we report a cathepsin L sequence identified from the constructed cDNA library of striped murrel Channa striatus (designated as CsCath L) using genome sequencing FLXTM technology. The full-length CsCath L contains three eukaryotic thiol protease domains at positions 134-145, 278-288 and 299-318. Phylogenetic analysis revealed that the CsCath L was clustered together with other cathepsin L from teleosts. The three-dimensional structure of CsCath L modelled by the I-Tasser program was compared with structures deposited in the Protein Data Bank to find out the structural similarity of CsCath L with experimentally identified structures. The results showed that the CsCath L exhibits maximum structural identity with pro-cathepsin L from human. The RNA fold structure of CsCath L was predicted along with its minimum free energy (−471.93 kcal/mol). The highest CsCath L gene expression was observed in liver, which was also significantly higher (P < 0.05) than that detected in other tissues taken for analysis. In order to investigate the mRNA transcription profile of CsCath L during infection, C. striatus were injected with fungus (Aphanomyces invadans) and bacteria (Aeromonas hydrophila) and its expression was up-regulated in liver at various time points. Similar to gene expression studies, the highest CsCath L enzyme activity was also observed in liver and its activity was up-regulated by fungal and bacterial infections.



2000 ◽  
Vol 33 (1) ◽  
pp. 176-183 ◽  
Author(s):  
Guoguang Lu

In order to facilitate the three-dimensional structure comparison of proteins, software for making comparisons and searching for similarities to protein structures in databases has been developed. The program identifies the residues that share similar positions of both main-chain and side-chain atoms between two proteins. The unique functions of the software also include database processingviaInternet- and Web-based servers for different types of users. The developed method and its friendly user interface copes with many of the problems that frequently occur in protein structure comparisons, such as detecting structurally equivalent residues, misalignment caused by coincident match of Cαatoms, circular sequence permutations, tedious repetition of access, maintenance of the most recent database, and inconvenience of user interface. The program is also designed to cooperate with other tools in structural bioinformatics, such as the 3DB Browser software [Prilusky (1998).Protein Data Bank Q. Newslett.84, 3–4] and the SCOP database [Murzin, Brenner, Hubbard & Chothia (1995).J. Mol. Biol.247, 536–540], for convenient molecular modelling and protein structure analysis. A similarity ranking score of `structure diversity' is proposed in order to estimate the evolutionary distance between proteins based on the comparisons of their three-dimensional structures. The function of the program has been utilized as a part of an automated program for multiple protein structure alignment. In this paper, the algorithm of the program and results of systematic tests are presented and discussed.



Author(s):  
Firoz Mv ◽  
Vishwanathan Balasubramanya Iyer ◽  
Vishal Gupta N ◽  
Gowda Dv ◽  
Gurupadayya Bm ◽  
...  

Objective: The importance of this research work is to design a library of novel coumarin derivatives by docking evaluation of the designed coumarin derivatives as squalene synthase inhibitor.Methods: The three-dimensional structure of designed molecules of squalene synthase inhibitors was collected from Protein Data Bank. The designed molecules were docked onto the enzymes that are squalene synthase inhibitor - 3WCM, 3WCJ, and 3Q2Z protein using SYBYL-X 2.1. Using a standard protocol, the protein was subjected to minimization and protomol generation.Results: By this method, we visualized the possible binding and also estimated the protein interactions with our intended coumarin library, using SYBYL-X 2.1 software. Into the active site of the selected enzymes, all the 20 coumarins were docked and then the docking scores revealed that the compounds possess high affinity toward the selected enzymes.Conclusion: With the help of virtual evaluation, we have elaborated a fast synthetically accessible coumarin-based compounds, and it is an advanced and original scaffold in the area of probable human squalene synthase inhibitors. Some of the developed compounds show better binding property than ligand, and in 3q2Z, the compound 5d shows better binding property than the protein. Furthermore, 6g and 6c have good binding property. In 3 WCM, the compound 6f has better property. In 3 WCJ, the compounds 6g and 6f show better binding property than the protein.



Author(s):  
Wei Li

Protein is the proteios building block of life. Evolutionarily, its sequence is not as conserved as its structure, making it more reasonable for protein structure, instead of protein sequence, to be the descriptor of protein function. Yet, in the National Center for Biotechnology Information (NCBI) database, the number of experimentally identified protein sequences is in great excess of that of experimentally determined protein structures inside the almost-half-a-century old Protein Data Bank (PDB). For instance, GPR151 is an proton-sensing G-protein coupled receptor (GPCR) originally identified as homologous to galanin receptors. As of March 19, 2020, GPR151&rsquo;s structure has not been experimentally determined and deposited in PDB yet. Thus, an ab initio modelling approach was employed here to build a three-dimensional structure of GPR151. Overall, the ab initio GPR151 model presented herein constitutes the first structural hypothesis of GPR151 to be experimentally tested in future with previously published, currently ongoing and future GPR151 studies.



Author(s):  
Monjur Ahmed Laskar ◽  
Manabendra Dutta Choudhury

Abstract Background: The global pandemic of novel coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an enveloped, positive-sense, single-stranded RNA betacoronavirus of the family Coronaviridae. Papain-like protease (PLpro) of SARS CoV-2 is an important target of COVID-19 because it is a multifunctional cysteine protease essential for coronaviral replication. Large numbers of phytochemicals with varied chemical structures isolated from medicinal plants have been shown to possess antiviral activity. Some of these phytochemicals have been chosen on the basis of literature survey for this study. Reported inhibitors of the papain-like protease are taken as control and for QSAR study.Methods: Three dimensional structure of target was downloaded from Protein Data Bank and docked with phytochemicals & inhibitors by using software FlexX. Inhibitors of the papain-like protease were taken from binding database and QSAR analysis was performed by using EasyQSAR software.Results: Six phytochemicals: Baicalin, Rutin, Biopterin, Licoleafol, Luteolin and Quercetin shows stable bonding pattern with the target in compare to known inhibitors as it shows least score in docking, forms maximum number of hydrogen bonds with the active residues of the receptor. The predicted IC50 values of the phytochemicals are also better than the known inhibitors.Conclusion: Based on present observation of docking score of both phytochemicals and known inhibitors, IC50 value of known inhibitors and predicted IC50 of phytochemicals, we suggests above mentioned six phytochemicals may be the Papain-like protease (PLpro) targeted potent drug leads against Covid-19.



2011 ◽  
Vol 44 (3) ◽  
pp. 647-650
Author(s):  
Venkatesh Babu ◽  
M. Uthayakumar ◽  
M. Kirti Vaishnavi ◽  
R. Senthilkumar ◽  
M. Shankar ◽  
...  

Repeats are two or more contiguous segments of amino acid residues that are believed to have arisen as a result of intragenic duplication, recombination and mutation events. These repeats can be utilized for protein structure prediction and can provide insights into the protein evolution and phylogenetic relationship. Therefore, to aid structural biologists and phylogeneticists in their research, a computing resource (a web server and a database), Repeats in Protein Sequences (RPS), has been created. Using RPS, users can obtain useful information regarding identical, similar and distant repeats (of varying lengths) in protein sequences. In addition, users can check the frequency of occurrence of the repeats in sequence databases such as the Genome Database, PIR and SWISS-PROT and among the protein sequences available in the Protein Data Bank archive. Furthermore, users can view the three-dimensional structure of the repeats using the Java visualization plug-inJmol. The proposed computing resource can be accessed over the World Wide Web at http://bioserver1.physics.iisc.ernet.in/rps/.



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