Staphylococcus aureus infection is a healthcare problem to mankind for a considerable period of time. Once when it enters the bloodstream of an individual, it may potentially result in ...life‐threatening conditions. The resistance of
S. aureus to various drugs such as penicillin, methicillin, gentamicin, erythromycin, and tetracycline have been well documented. Presently vancomycin is the drug of choice for methicillin resistant
S. aureus. Scientists believe that
S. aureus would completely develop resistance to vancomycin as well. Therefore there is a commensurate need to develop a drug to replace vancomycin. In the current study, we have focussed on FtsA, an important and vital cell division protein, which is found only in
S. aureus and in other prokaryotic cells. We have carried out virtual screening process for FtsA against ZINC database, the best hit molecules obtained from the preliminary docking studies were subjected to SYBYL X 2.0 docking. The molecules ZINC74432848, ZINC37769607, and ZINC96896268 displayed the highest C‐score value of 4.89, 4.49, and 4.22, respectively. The top ranked molecule ZINC74432848 was observed to form 4 hydrogen bonds with FtsA. The simulation study reveals the greater stability of the FtsA‐ZINC74432848 complex. If the in vitro and in vivo study turns out affirmative, then ZINC74432848 could be developed as a potent drug for FtsA.
The Staphylococcus aureus‐related infections have been a threat to the mankind for a very long time. Over the period of time
S. aureus strains developed resistance to various antibiotics. The present work focused on developing a novel drug against FtsA, which is very much essential for the survival of
S. aureus. Since it is not found in eukaryotes, there could be potentially no side effects. The ZINC74432848 compound was found to be the best inhibitor of
S. aureus FtsA protein based on docking studies. The simulation study emphasizes the fact that ZINC74432848 compound has a stable interaction with
S. aureus FtsA protein.
The World Health Organization reports that millions of people around the world are infected with antibiotic‐resistant bacteria. Such resistance is more common in Pseudomonas aeruginosa, Acinetobacter ...baumannii, and Klebsiella pneumoniae strains because of the expression of the metallo‐β‐lactamases (MBLs) namely Imipenemase (IMP)‐1, IMP‐2, New Delhi metallo‐β‐lactamases‐, Verona imipenemase (VIM)‐4, VIM‐5, and VIM‐7. We did an in silico analysis to understand the resistance mechanism of imipenem at the structural level. Our modeling studies reveal that the VIM‐4‐imipenem complex has highest binding energy and forms a stable complex as indicated by a consensus score (C‐score) value of 5.44. The intense interaction between the substrate and the β‐lactamases leads to the increased hydrolysis of the substrate resulting in rapid hydrolysis of the antibiotic imipenem by VIM‐4. Virtual screening of compounds from the ZINC database targeting VIM‐4 was done, and we found compound ZINC44608383 as the high binding energy compound with the C‐score value of 5.58. This compound could be exploited for inhibitor design and development. The current study helps us to understand the resistance mechanism of imipenem in MBL‐expressing strains. Also, we have identified a probable inhibitor for VIM‐4. We believe that our results will be useful for researchers in designing potent inhibitors for VIM‐4.
The compounds ZINC44608383, ZINC63887176, and ZINC39962616 have consensus score (C‐score) values of 5.58, 3.57, and 1.12, respectively. These three compounds were chosen as the best binding energy compounds depending on the C‐score value and the formation of H‐bonds.
Cholera is a serious threat to a large population in the under developed countries. Though oral rehydration therapy is the preferred choice of treatment, the use of antibiotics could reduce the ...microbial load in the case of severity. The use of antibiotics is also sought in the scenarios where there is problem with access to clean water. However, Vibrio cholera (V. cholerae) strains have developed resistance to antibiotics such as amoxicillin, ampicillin, chloramphenicol, doxycycline, erythromycin, and tetracycline. In this work, we have addressed the resistance issue by targeting MurB protein which is essential for the cell wall biosynthesis in V. cholerae. 20 Phytochemical compounds were chosen to screen the potential inhibitors against V. cholerae to avoid the complications faced by synthesis of small molecules. The molecular docking and dynamics study indicates that quercetin is the most potential and stable inhibitor of Murb.
MurB was found to be unique in Vibrio cholerae (V. cholerae) and hence it was considered as drug target for this study. Quercetin was found to be the best inhibitor of V. cholerae MurB. GROMACS simulation results suggested that quercetin had a stable interaction with V. cholerae MurB.
Presently, there are no effective vaccines and anti-virals for the prevention and treatment of Hepatitis C virus infections and hence there is an urgent need to develop potent HCV inhibitors. In this ...study, we have carried out molecular docking, molecular dynamics and 3D-QSAR on heteroaryl 3-(1,1-dioxo-2H-(1,2,4)-benzothiadizin-3-yl)-4-hydroxy-2(1H)-quinolinone series using NS5B protein. Total of 41 quinolinone derivatives is used for molecular modeling study. The binding conformation and hydrogen bond interaction of the docked complexes were analyzed to model the inhibitors. We identified the molecule XXXV that had a higher affinity with NS5B. The molecular dynamics study confirmed the stability of the compound XXXV-NS5B complex. The developed CoMFA descriptors parameters, which were calculated using a test set of 13 compounds, were statistically significant. Our results will provide useful insights and lead to design potent anti-Hepatitis C virus molecules.
The wild-type SARS-CoV-2 has continuously evolved into several variants with increased transmissibility and virulence. The Delta variant which was initially identified in India created a devastating ...impact throughout the country during the second wave. While the efficacy of the existing vaccines against the latest SARS-CoV-2 variants remains unclear, extensive research is being carried out to develop potential antiviral drugs through approaches like in silico screening and drug-repurposing. This study aimed to conduct the docking-based virtual screening of 50 potential phytochemical compounds against a Spike glycoprotein of the wild-type and the Delta SARS-CoV-2 variant. Subsequently, molecular docking was performed for the five best compounds, such as Lupeol, Betulin, Hypericin, Corilagin, and Geraniin, along with synthetic controls. From the results obtained, it was evident that Lupeol exhibited a remarkable binding affinity towards the wild-type Spike protein (-8.54 kcal/mol), while Betulin showed significant binding interactions with the mutated Spike protein (-8.83 kcal/mol), respectively. The binding energy values of the selected plant compounds were slightly higher than that of the controls. Key hydrogen bonding and hydrophobic interactions of the resulting complexes were visualized, which explained their greater binding affinity against the target proteins-the Delta S protein of SARS-CoV-2, in particular. The lower RMSD, the RMSF values of the complexes and the ligands, Rg, H-bonds, and the binding free energies of the complexes together revealed the stability of the complexes and significant binding affinities of the ligands towards the target proteins. Our study suggests that Lupeol and Betulin could be considered as potential ligands for SARS-CoV-2 spike antagonists. Further experimental validations might provide new insights for the possible antiviral therapeutic interventions of the identified lead compounds and their analogs against COVID-19 infection.
The high incidences of COVID-19 cases are believed to be associated with high transmissibility rates, which emphasizes the need for the discovery of evidence-based antiviral therapies for curing the ...disease. The rationale of repurposing existing classes of antiviral small molecule therapeutics against SARS-CoV-2 infection has been expected to accelerate the tedious and expensive drug development process. While Remdesivir has been recently approved to be the first treatment option for specific groups of COVID-19 patients, combinatory therapy with potential antiviral drugs may be necessary to enhance the efficacy in different populations. Hence, a comprehensive list of investigational antimicrobial drug compounds such as Favipiravir, Fidaxomicin, Galidesivir, GC376, Ribavirin, Rifabutin, and Umifenovir were computationally evaluated in this study. We performed in silico docking and molecular dynamics simulation on the selected small molecules against RNA-dependent RNA polymerase, which is one of the key target proteins of SARS-CoV-2, using AutoDock and GROMACS. Interestingly, our results revealed that the macrocyclic antibiotic, Fidaxomicin, possesses the highest binding affinity with the lowest energy value of −8.97 kcal/mol binding to the same active sites of RdRp. GC376, Rifabutin, Umifenovir and Remdesivir were identified as the next best compounds. Therefore, the above-mentioned compounds could be considered good leads for further preclinical and clinical experimentations as potentially efficient antiviral inhibitors for combination therapies against SARS-CoV-2.
Despite the fact that cervical cancer is preventable and curable in the early stages, it still remains to be a major public health problem in India. This study was conducted to assess the knowledge ...and awareness regarding the Human Papilloma Virus (HPV) vaccination among health care professionals working in a tertiary care hospital in urban India.
To this aim, we conducted a cross-sectional study among 318 health care professionals working in tertiary hospitals across Chennai, Tamil Nadu, India. Our research group designed a structured questionnaire with 31 items to assess the knowledge and attitudes on cervical cancer, its prevention, and HPV vaccination.
Among the 318 respondents, 90.6% were aware of cervical cancer, 83.3% were aware that PAP (Papanicolaou) smear test detects cervical cancer, and 86.2% of the respondents knew that HPV causes cervical cancer. 29.2% of the eligible respondents underwent the screening against cervical cancer, and 19.8% of the study participants were vaccinated for HPV. Only 34.9% know that the HPV vaccine could be given to boys. The most common reason for not being vaccinated against HPV was the lack of awareness. In our study, 77.2% of the respondents were willing to be vaccinated and recommend HPV vaccination to their family members.
From this study, it was evident that there is a lack of awareness about HPV vaccination and its importance in preventing cervical cancer among healthcare professionals. Our finding clearly establishes the need to devise intervention programs to promote vaccination against HPV and periodical screening for cervical cancer among healthcare professionals.
Background
Mammosphere formation assay has become a versatile tool to quantify the activity of putative breast cancer stem cells in non-adherent in vitro cultures. However, optimizing the suspension ...culture system is crucial to establish mammosphere cultures from primary breast tumors.
Methods
This study aimed at determining the self-renewal and sphere-forming potential of breast cancer stem-like cells derived from human primary invasive ductal carcinoma and normal breast tissue samples, and MCF-7 breast cancer cell line using an optimal suspension culture system. Mammosphere-forming efficiency of the mammospheres generated from the tissue samples and cell line were compared. We evaluated the expression of CD44
+
/CD24
−
/
low
and CD49f
+
/EpCAM
−
/
low
phenotypes in the stem-like cells by flow cytometry. CK-18, CK-19, α-SMA, and EpCAM marker expression was assessed using immunohistochemical staining.
Results
Breast epithelial cells isolated from the three samples formed two-dimensional spheroids in suspension cultures. Interestingly, mammospheres formed from patient-derived primary breast tumors were enriched in breast cancer stem-like cells with the phenotype CD44
+
/CD24
−
/
low
and exhibited a relatively more number of large spheres when compared to the normal breast stem cells. MCF-7-derived SCs were more aggressive and resulted in the formation of a significantly higher number of spheroids. The expression of CK-18/CK-19 and α-SMA/EpCAM proteins was confirmed in breast cancer tissues.
Conclusions
Thus, the use of primary tumor specimens and breast cancer cell lines as suitable models for elucidating the breast cancer stem cell activity was validated using mammosphere culture system.
Prolonged antibiotic therapy for the bacterial infections has resulted in high levels of antibiotic resistance. Initially, bacteria are susceptible to the antibiotics, but can gradually develop ...resistance. Treating such drug-resistant bacteria remains difficult or even impossible. Hence, there is a need to develop effective drugs against bacterial pathogens. The drug discovery process is time-consuming, expensive and laborious. The traditionally available drug discovery process initiates with the identification of target as well as the most promising drug molecule, followed by the optimization of this, in-vitro, in-vivo and in pre-clinical studies to decide whether the compound has the potential to be developed as a drug molecule. Drug discovery, drug development and commercialization are complicated processes. To overcome some of these problems, there are many computational tools available for new drug discovery, which could be cost effective and less time-consuming. In-silico approaches can reduce the number of potential compounds from hundreds of thousands to the tens of thousands which could be studied for drug discovery and this results in savings of time, money and human resources. Our review is on the various computational methods employed in new drug discovery processes.
The current dynamics of the COVID-19 pandemic have become a serious concern with the emergence of a series of mutant variants of the SARS-CoV-2 virus. Unlike the previous strain, it is reported that ...the descendants are associated with increased risk of transmission yet causing less impact in terms of hospital admission, the severity of illness, or mortality. Moreover, the vaccine efficacy is also not believed to vary among the population depending on the variants of the virus and ethnicity. It has been determined that the mutations recorded in the spike gene and protein of the newly evolved viruses are specificallyresponsible for this transformation in the behavior of the virus and its disease condition. Hence, this study aimed to compare the immunogenic profiles of the spike protein from the latest variants of the SARS-CoV-2 virus concerning the probability of COVID-19 severity. Genome sequences of the latest SARS-CoV-2 variants were obtained from GISAID and NCBI repositories. The translated protein sequences were run against T-cell and B-cell epitope prediction tools. Subsequently, antigenicity, immunogenicity, allergenicity, toxicity, and conservancy of the identified epitopes were ascertained using various prediction servers. Only the non-allergic and non-toxic potential epitopes were matched for population relevance by using the Human Leucocyte Antigen population registry in IEDB. Finally, the selected epitopes were validated by docking and simulation studies. The evaluated immunological parameters would concurrently reveal the severity of COVID-19, determining the infection rate of the pathogen. Our immunoinformatics approach disclosed that spike protein of the five variants was capable of forming potential T and B-cell epitopes with varying immune responses. Although the Wuhan strain showed a high number of epitope/HLA combinations, relatively less antigenicity and higher immunogenicity results in poor neutralizing capacity, which could be associated with increased disease severity. Our data demonstrate that increased viral antigenicity with moderate to high immunogenicity, and several potential epitope/HLA combinations in England strain, the USA, India, and South Africa variants, could possess a high neutralizing ability. Therefore, our findings reinforce that the newly circulating variants of SARS-CoV-2 might be associated with more infectiousness and less severe disease condition despite their greater viremia, as reported in the recent COVID-19 cases, whichconsequently determine their increased epidemiological fitness.
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