Shedding light on cancer immunology at the molecular level: A quantum biochemistry study of representative PD-1/PD-L1 conformations.

Background: Programmed death 1 (PD-1) binding to PD-L1 is a potent mechanism used by immunogenic tumors to evade the immune system and the immune checkpoint PD-1PD-L1 has emerged as a promising target in the search for new drugs to improve cancer treatment. The crystallographic structure of PD-1PD-L1 shed light on the molecular characterization of this system and allowed computational studies to be carried out to characterize structural behaviors.

Methods: This study demonstrated the importance of analyzing the flexibility of protein systems through molecular dynamics simulations (MDS) and its impacts on the interaction energy obtained through quantum biochemistry.

approach revealed the membrane receptor PHO36 as a new target for synthetic anticandidal peptides.

Synthetic antimicrobial peptides (SAMPs) present the potential to fight systemic fungal infections. Here, the PHO36 receptor from was analyzed by tools as a possible target for three anticandidal SAMPs: Alb-PepIII, PepGAT and PepKAA. Molecular docking, dynamics and quantum biochemistry were employed to understand the individual contribution of amino acid residues in the interaction region.

Tofacitinib and peficitinib inhibitors of Janus kinase for autoimmune disease treatment: a quantum biochemistry approach.

Autoimmune inflammatory diseases, such as rheumatoid arthritis (RA) and ulcerative colitis, are associated with an uncontrolled production of cytokines leading to the pronounced inflammatory response of these disorders. Their therapy is currently focused on the inhibition of cytokine receptors, such as the Janus kinase (JAK) protein family. Tofacitinib and peficitinib are JAK inhibitors that have been recently approved to treat rheumatoid arthritis.

analysis of from different animal species provides new insights into SARS-CoV-2 species spillover.

This study aimed to analyze the phylogenetic relationships between the ACE2 of humans and other animals and investigate the potential interaction between SARS-CoV-2 RBD and ACE2 of different species. The phylogenetic construction and molecular interactions were assessed using computational models. Despite the evolutionary distance, 11 species had a perfect fit for the interaction between their ACE2 and SARS-CoV-2 RBD (, , , ).

Characterization of the binding interaction between atrazine and human serum albumin: Fluorescence spectroscopy, molecular dynamics and quantum biochemistry.

Atrazine (ATR), one of the most used herbicides worldwide, causes persistent contamination of water and soil due to its high resistance to degradation. ATR is associated with low fertility and increased risk of prostate cancer in humans, as well as birth defects, low birth weight and premature delivery. Describing ATR binding to human serum albumin (HSA) is clinically relevant to future studies about pharmacokinetics, pharmacodynamics and toxicity of ATR, as albumin is the most abundant carrier protein in plasma and binds important small biological molecules.

Combined antibiofilm activity of synthetic peptides and antifungal drugs against spp.

and are biofilm-forming drug-resistant yeasts that cause bloodstream infections that can lead to death. nystatin and itraconazole were combined with two synthetic peptides, PepGAT and PepKAA, to evaluate the synergistic effect against biofilms. Additionally, scanning electron and fluorescence microscopies were employed to understand the mechanism behind the synergistic activity.

Synergistic Antifungal Activity of Synthetic Peptides and Antifungal Drugs against and Biofilms.

and are biofilm-forming yeasts responsible for bloodstream infections that can cause death. Synthetic antimicrobial peptides (SAMPs) are considered to be new weapons to combat these infections, alone or combined with drugs. Here, two SAMPs, called -CBP-PepI and -CBP-PepIII, were tested alone or combined with nystatin (NYS) and itraconazole (ITR) against and biofilms.

Neutralizing Effect of Synthetic Peptides toward SARS-CoV-2.

The outbreak caused by SARS-CoV-2 has taken many lives worldwide. Although vaccination has started, the development of drugs to either alleviate or abolish symptoms of COVID-19 is still necessary. Here, four synthetic peptides were assayed regarding their ability to protect Vero E6 cells from SARS-CoV-2 infection and their toxicity to human cells and zebrafish embryos.

The spike glycoprotein of SARS-CoV-2: A review of how mutations of spike glycoproteins have driven the emergence of variants with high transmissibility and immune escape.

Late in 2019, SARS-CoV-2 (severe acute respiratory syndrome coronavirus-2) emerged, causing an unknown type of pneumonia today called coronaviruses disease 2019 (COVID-19). COVID-19 is still an ongoing global outbreak that has claimed and threatened many lives worldwide. Along with the fastest vaccine developed in history to fight SARS-CoV-2 came a critical problem, SARS-CoV-2.

Synthetic antimicrobial peptides control Penicillium digitatum infection in orange fruits.

Fungal contamination is among the main reasons for food spoilage, affecting food safety and the economy. Among fungi, Penicillium digitatum is a major agent of this problem. Here, the in vitro activity of eight synthetic antimicrobial peptides was assessed against P.

Computational approach, scanning electron and fluorescence microscopies revealed insights into the action mechanisms of anticandidal peptide Mo-CBP-PepIII.

Aims: The Candida genus is composed of opportunistic pathogens that threaten public health. Given the increase in resistance to current drugs, it is necessary to develop new drugs to treat infections by these pathogens. Antimicrobial peptides are promising alternative molecules with low cost, broad action spectrum and low resistance induction.

Kinase inhibitor screening reveals aurora-a kinase is a potential therapeutic and prognostic biomarker of gastric cancer.

Gastric cancer is one of the most common and deadly types of cancer in the world, and poor prognosis with treatment failure is widely reported in the literature. In this context, kinases have been considered a relevant choice for targeted therapy in gastric cancer. Here, we explore the antiproliferative and antimigratory effects of the AURKA inhibitor and the prognostic and therapeutic value as a biomarker of gastric cancer.

Synthetic antimicrobial peptides: Characteristics, design, and potential as alternative molecules to overcome microbial resistance.

Recently, the dramatic emergence of antimicrobial resistance has received attention from World Health Organization. Synthetic antimicrobial peptides (SAMPs) are considered new weapons to fight against infections caused by multi-drug resistant pathogens. Here, the authors provide an overview of the current research on SAMPs.

Molecular insight on the binding of stevia glycosides to bovine serum albumin.

The interaction of the steviol and its glycosides (SG), steviolbioside, and rebaudioside A, with bovine serum albumin (BSA) was studied by absorption and fluorescence spectroscopy techniques alongside molecular docking. The stevia derivatives quenched the fluorescence of BSA by a dynamic quenching mechanism, indicating the interaction between the stevia derivatives and BSA. The binding constant (K) of steviol was 100-1000-fold higher than those of SG.

Quantum biochemistry, molecular docking, and dynamics simulation revealed synthetic peptides induced conformational changes affecting the topology of the catalytic site of SARS-CoV-2 main protease.

The recent outbreak caused by SARS-CoV-2 continues to threat and take many lives all over the world. The lack of an efficient pharmacological treatments are serious problems to be faced by scientists and medical staffs worldwide. In this work, an approach based on the combination of molecular docking, dynamics simulations, and quantum biochemistry revealed that the synthetic peptides -PepI, PepGAT, and PepKAA, strongly interact with the main protease (Mpro) a pivotal protein for SARS-CoV-2 replication.

The human pandemic coronaviruses on the show: The spike glycoprotein as the main actor in the coronaviruses play.

Three coronaviruses (CoVs) have threatened the world population by causing outbreaks in the last two decades. In late 2019, the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) emerged and caused the coronaviruses to disease 2019 (COVID-19), leading to the ongoing global outbreak. The other pandemic coronaviruses, SARS-CoV and Middle East respiratory syndrome CoV (MERS-CoV), share a considerable level of similarities at genomic and protein levels.

ACE2-derived peptides interact with the RBD domain of SARS-CoV-2 spike glycoprotein, disrupting the interaction with the human ACE2 receptor.

Vaccines could be the solution to the current SARS-CoV-2 outbreak. However, some studies have shown that the immunological memory only lasts three months. Thus, it is imperative to develop pharmacological treatments to cope with COVID-19.

Quantum biochemistry in cancer immunotherapy: New insights about CTLA-4/ipilimumab and design of ipilimumab-derived peptides with high potential in cancer treatment.

Cancer is a group of diseases involving disordered growth of abnormal cells with the potential to invade and spread to other parts of the body. Today, immunotherapy is the most efficient treatment, with fewer side effects. Notably, the employment of monoclonal antibodies to inhibit checkpoint proteins, such as CTLA-4, has caused much excitement among cancer immunotherapy researchers.

A molecular docking study revealed that synthetic peptides induced conformational changes in the structure of SARS-CoV-2 spike glycoprotein, disrupting the interaction with human ACE2 receptor.

The global outbreak of COVID-19 (Coronavirus Disease 2019) caused by SARS-CoV-2 (Severe Acute Respiratory Syndrome caused by Coronavirus 2) began in December 2019. Its closest relative, SARS-CoV-1, has a slightly mutated Spike (S) protein, which interacts with ACE2 receptor in human cells to start the infection. So far, there are no vaccines or drugs to treat COVID-19.

Insights into milk-clotting activity of latex peptidases from Calotropis procera and Cryptostegia grandiflora.

Latex fractions from Calotropis procera, Cryptostegia grandiflora, Plumeria rubra, and Himatanthus drasticus were assayed in order to prospect for new plant peptidases with milk-clotting activities, for use as rennet alternatives. Only C. procera and C.