Biology subjects

Barh, D.

Publications and source records attributed to Barh, D..

7 recordsLinked to original sources

bioRxiv2024

Molecular Genomic Insights into Melanoma Associated Proteins PRAME and BAP1

BackgroundMelanoma, a worldwide widespread skin cancer with over 325,000 yearly incidences, demands a thorough understanding of its molecular components to create effective therapeutics. This study looks at the PRAME (cutaneous melanoma-associated antigen) and BAP1 (gene controlling gene-environment interactions) proteins, which are important in melanoma development and are important for understanding the molecular landscape of melanoma. IntroductionWhile playing a crucial role in melanoma, the structural and functional characteristics of PRAME and BAP1 remain unidentified. This work tries to unravel their complexities by investigating conserved residues, sequence invariance, and other molecular characteristics that contribute to their importance in melanoma. Promising therapeutic targets for melanoma therapy are identified by analyzing these proteins at the molecular level. MethodsThe study makes extensive use of bioinformatics methods to analyze PRAME and BAP1, including sequence conservation, inherent disorder, polyglutamic acid presence, and polarity alterations. Established approaches are used to investigate residue changes and their effects on protein folding, aggregation, and interactions. ResultsPRAME and BAP1 conserved residues highlight their critical roles in protein function and interaction. Sequence invariance indicates the possibility of functional relevance and evolutionary conservation. In intrinsically disordered proteins (IDPRs), PRAME has enhanced intrinsic disorder and flexibility, whereas BAP1 has changed disorder-promoting residue sequences. Polyglutamic acid strings are found in both proteins, emphasizing their modulatory involvement in protein interactions. Protein folding and aggregation are influenced by polarity shifts, with a balanced distribution of acidic and basic residues preserving native structures. The ratios and distributions of amino acids, particularly neutral residues, have a profound influence on interactions and gene dysregulation. ConclusionPRAME and BAP1 structural and functional understanding pave the way for diagnostic and tailored treatment options in melanoma. Differences in residue alterations, polarity distributions, and amino acid ratios provide intriguing drug design options. This research contributes to a better knowledge of melanoma-associated two proteins, opening the path for novel diagnostic and therapy techniques in skin cancer and beyond.

bioinformatics↗

bioRxiv2023

SARS-CoV-2 NSP14 governs mutational instability and assists in making new SARS-CoV-2 variants

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the rapidly evolving RNA virus behind the COVID-19 pandemic, has spawned numerous variants since its 2019 emergence. The multifunctional NSP14 enzyme, possessing exonuclease and mRNA capping capabilities, serves as a key player. Notably, single and co-occurring mutations within NSP14 significantly influence replication fidelity and drive variant diversification. This study comprehensively examines 120 co-mutations, 68 unique mutations, and 160 conserved residues across NSP14 homologs, shedding light on their implications for phylogenetic patterns, pathogenicity, and residue interactions. Quantitative physicochemical analysis categorizes 3953 NSP14 variants into three clusters, revealing genetic diversity. This research underscores the dynamic nature of SARS-CoV-2 evolution, primarily governed by NSP14 mutations. Understanding these genetic dynamics provides valuable insights for therapeutic and vaccine development.

bioinformatics↗

bioRxiv2022

SARS-CoV-2 variants show a gradual declining pathogenicity and pro-inflammatory cytokine stimulation and an increasing antigenic and anti-inflammatory cytokine induction

Hyper-transmissibility with decreased disease severity are typical characteristics of Omicron variant. To understand this phenomenon, we used various bioinformatics approaches to analyze randomly selected genome sequences (one each) of the Gamma, Delta, and Omicron variants submitted to NCBI from 15 to 31 December 2021. We show that: (i) Pathogenicity of SARS-CoV-2 variants decreases in the order: Wuhan > Gamma > Delta > Omicron; however, the antigenic property follows the order: Omicron > Gamma > Wuhan > Delta. (ii) Omicron Spike RBD has lower pathogenicity but higher antigenicity than other variants. (iii) Decreased disease severity by Omicron variant may be due to its decreased pro-inflammatory and IL-6 stimulation and increased IFN-{gamma} and IL-4 induction efficacy. (iv) Mutations in N protein are associated with decreased IL-6 induction and human DDX21-mediated increased IL-4 production in Omicron. (v) Due to mutations, the stability of S, M, N, and E proteins decreases in the order: Omicron > Gamma > Delta > Wuhan. (vi) Stronger Spike RBD-hACE2 binding in Omicron is associated with increased transmissibility. However, the lowest stability of the Omicron Spike protein makes Spike RBD-hACE2 interaction weak for systemic infection and for causing severe disease. Finally (vii), the highest instability of Omicron E protein may also be associated with decreased viral maturation and low viral load leading to less severe disease and faster recovery. Our method may be used for other similar viruses, and these findings will contribute to the understanding of the dynamics of SARS-CoV-2 variants and the management of emerging variants.

bioinformatics↗

bioRxiv2021

An Issue of Concern: Unique Truncated ORF8 Protein Variants of SARS-CoV-2

Open reading frame 8 (ORF8) protein is one of the most evolving accessory proteins in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19). It was previously reported that the ORF8 protein inhibits presentation of viral antigens by the major histocompatibility complex class I (MHC-I) and interacts with host factors involved in pulmonary inflammation. The ORF8 protein assists SARS-CoV-2 to evade immunity and replication. Among many contributing mutations, Q27STOP, a mutation in the ORF8 protein defines the B.1.1.7 lineage of SARS-CoV-2, which is engendering the second wave of COVID-19. In the present study, 47 unique truncated ORF8 proteins (T-ORF8) due to the Q27STOP mutations were identified among 49055 available B.1.1.7 SARS-CoV-2 sequences. The results show that only one of the 47 T-ORF8 variants spread to over 57 geo-locations in North America, and other continents which includes Africa, Asia, Europe and South America. Based on various quantitative features such as amino acid homology, polar/non-polar sequence homology, Shannon entropy conservation, and other physicochemical properties of all specific 47 T-ORF8 protein variants, a collection of nine possible T-ORF8 unique variants were defined. The question of whether T-ORF8 variants work similarly to ORF8 has yet to be investigated. A positive response to the question could exacerbate future COVID-19 waves, necessitating severe containment measures.

bioinformatics↗

bioRxiv2021

Implications Derived from S-Protein Variants of SARS-CoV-2 from Six Continents

Spike (S) proteins of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are critical determinants of the infectivity and antigenicity of the virus. Several mutations in the spike protein of SARS-CoV-2 have already been detected, and their effect in immune system evasion and enhanced transmission as a cause of increased morbidity and mortality are being investigated. From pathogenic and epidemiological perspectives, spike proteins are of prime interest to researchers. This study focused on the unique variants of S proteins from six continents Asia, Africa, Europe, Oceania, South America, and North America. In comparison to the other five continents, Africa (29.065%) had the highest percentage of unique S proteins. Notably, only North America had 87% (14046) of the total (16143) specific S proteins available in the NCBI database(across all continents). Based on the amino acid frequency distributions in the S protein variants from all the continents, the phylogenetic relationship implies that unique S proteins from North America were significantly different from those of the other five continents. Overtime, the unique variants originating from North America are most likely to spread to the other geographic locations through international travel or naturally by emerging mutations. Hence it is suggested that restriction of international travel should be considered, and massive vaccination as an utmost measure to combat the spread of COVID-19 pandemic. It is also further suggested that the efficacy of existing vaccines and future vaccine development must be reviewed with careful scrutiny, and if needed, further re-engineered based on requirements dictated by new emerging S protein variants.

bioinformatics↗

bioRxiv2020

Taxonomic classification of strain PO100/5 shows a broader geographic distribution and genetic markers of the recently described Corynebacterium silvaticum

The bacterial strain PO100/5 was isolated from a skin abscess of a pig (Sus scrofa domesticus) in the Alentejo region of southern Portugal. It was identified as Corynebacterium pseudotuberculosis using biochemical tests, multiplex PCR and Pulsed Field Gel Electrophoresis. After genome sequencing and rpoB phylogeny, the strain was classified as C. ulcerans. To better understand the taxonomy of this strain and improve identification methods, we compared strain PO100/5 to other publicly available genomes from the C. diphtheriae group. Taxonomic analysis reclassified it and three others strains as belonging to the recently described C. silvaticum, which have been isolated from wild boar and roe deer in Germany and Austria. The results showed that PO100/5 is the first sequenced genome of a C. silvaticum strain from a domestic animal and a different geographical region, is a putative producer of the diphtheriae toxin, and has a unique sequence type. Genomic analysis of PO100/5 showed four prophages and eight conserved genomic islands when compared to C. ulcerans. Pangenome analysis of 38 C. silvaticum and 76 C. ulcerans samples suggest that C. silvaticum is a clonal species, with 73.6% of conserved genes and a pangenome near to being closed ( > 0.952). 172 conserved genes are unique to C. silvaticum when compared to C. ulcerans, with most related to nutrient uptake and metabolism, prophages or immune evasion. These unique genes could be used as genetic markers for species identification. This information can be useful for identification and surveillance of this pathogen, especially in regard to the possibility of zoonotic transmission.

genomics↗

bioRxiv2017

A potential link between tuberculosis and lung cancer through non-coding RNAs

Pulmonary tuberculosis caused by Mycobacterium and lung cancer are two major causes of deaths worldwide and the former increases the risk of developing lung cancer. However, the precise molecular mechanism of Mycobacterium associated increased risk of lung cancer is not entirely understood. Here, using in silico approaches, we show that hsa-mir-21 and M. tuberculosis sRNA_1096 and sRNA_1414 could play important roles in the pathogenesis of both these diseases. Further, we postulated a \"Genetic remittance\" hypothesis where these sRNAs may play important roles. The sRNA_1096 could be involved in tuberculosis through multiple infectious processes, and if transferred to the host, it may activate the TLR8 mediated pro-metastatic inflammatory pathway by acting as a ligand to TLR8 similar to the mir-21 leading to lung tumorigenesis and chemo-resistance. Analogous to SH3GL1, it may also regulate cell cycle. On the other hand, sRNA_1414 is probably involved in survivability and drug response of the pathogen. However, it may be a metastatic factor for lung cancer providing EPS8L1 and SORBS1 like functions upon remittance. Further, all these three non-coding RNAs are predicted to act in rifampicin resistance in Mycobacterium. Currently, we are applying robust bioinformatics strategies and conducting experimental validations to confirm our in-silico findings and hypothesis.

cancer biology↗