Synthesis of Neurolysin Modulators for Stroke and Cancer Treatment

Neurolysin (Nln) is a neutral metalloendopeptidase, which is an enzyme that breaks down peptide bonds in amino acids whilst ultilizing a metal catalyst1. Nln inactivates several neuro/cerberotoxic neuropeptides such as neurotensin, substance P, and bradykinin2. These neuropeptides can cause harm to the brain as they respond to inflammation during an ischemic stroke3,4. The peptides generated by Nln are neuro/cerebroprotective which aids in its ability to protect the brain in an ischemic stroke victim2. The goal of our lab is to discover a potent neurolysin activator in order to develop a drug that protect victims from brain damage and disability following an ischemic stroke. To begin this process, our lab successfully designed, synthesized, and established the structure-activity relationships of several potential neurolysin activators via a preliminary neurolysin activation assay on several targeted compounds. Secondary amine analogs were created and synthesized to test their neurolysin activation potential. The goals of this experiment are to resynthesize these compounds to gather additional NMR and HPLC data and to optimize the reaction to obtain a pure compound with a substantial yield.https://digitalcommons.unmc.edu/surp2022/1007/thumbnail.jp

Genetically encoded FRET-based optical sensor for Hg2+ detection and intracellular imaging in living cells

Abstract Due to the potential toxicity of mercury, there is an immediate need to understand its uptake, transport and flux within living cells. Conventional techniques used to analyze Hg2+ are invasive, involve high cost and are less sensitive. In the present study, a highly efficient genetically encoded mercury FRET sensor (MerFS) was developed to measure the cellular dynamics of Hg2+ at trace level in real time. To construct MerFS, the periplasmic mercury-binding protein MerP was sandwiched between enhanced cyan fluorescent protein (ECFP) and venus. MerFS is pH stable, offers a measurable fluorescent signal and binds to Hg2+ with high sensitivity and selectivity. Mutant MerFS-51 binds with an apparent affinity (K  d) of 5.09 × 10−7 M, thus providing a detection range for Hg2+ quantification between 0.210 µM and 1.196 µM. Furthermore, MerFS-51 was targeted to Escherichia coli (E. coli), yeast and human embryonic kidney (HEK)-293T cells that allowed dynamic measurement of intracellular Hg2+ concentration with a highly responsive saturation curve, proving its potential application in cellular systems.</jats:p

Synthesis, Antimicrobial Evaluation and In silico Studies of Novel 2,4- disubstituted-1,3-thiazole Derivatives

Background: 2,4-disubstituted-1,3-thiazole derivatives (2a–j), (3a–f) and (4a–f) were synthesized, characterized and screened for their potential as antimicrobial agents. In the preliminary screening against a panel of bacterial strains, nine compounds showed moderate to potent antibacterial activity (IC50 = 13.7-90.8 μg/ml). &lt;/P&gt;&lt;P&gt; Methods: In the antifungal screening, compound (4c) displayed potent antifungal activity (IC50 = 26.5 &amp;#181;g/ml) against Candida tropicalis comparable to the standard drug, fluconazole (IC50 = 10.5 &amp;#181;g/ml). Based on in vitro antimicrobial results, compounds 2f, 4c and 4e were selected for further pharmacological investigations. Hemolytic activity using human red blood cells (hRBCs) and cytotoxicity by MTT assay on human embryonic kidney (HEK-293) cells revealed non-toxic nature of the selected compounds (2f, 4c and 4e). To ascertain their possible mode of action, docking studies with the lead inhibitors (2f, 4c and 4e) were performed using crystal structure coordinates of bacterial methionine aminopeptidases (MetAPs), an enzyme involved in bacterial protein synthesis and maturation. Results: The results of in vitro and in silico studies provide a rationale for selected compounds (2f, 4c and 4e) to be carried forward for further structural modifications and structure-activity relationship (SAR) studies against these bacterial infections. Conclusion: The study suggested binding with one or more key amino acid residues in the active site of Streptococcus pneumoniae MetAP (SpMetAP) and Escherichia coli MetAP (EcMetAP). In silico physicochemical properties using QikProp confirmed their drug likeliness. </jats:sec

Structural Features of Nucleoprotein CST/Shelterin Complex Involved in the Telomere Maintenance and Its Association with Disease Mutations

Telomere comprises the ends of eukaryotic linear chromosomes and is composed of G-rich (TTAGGG) tandem repeats which play an important role in maintaining genome stability, premature aging and onsets of many diseases. Majority of the telomere are replicated by conventional DNA replication, and only the last bit of the lagging strand is synthesized by telomerase (a reverse transcriptase). In addition to replication, telomere maintenance is principally carried out by two key complexes known as shelterin (TRF1, TRF2, TIN2, RAP1, POT1, and TPP1) and CST (CDC13/CTC1, STN1, and TEN1). Shelterin protects the telomere from DNA damage response (DDR) and regulates telomere length by telomerase; while, CST govern the extension of telomere by telomerase and C strand fill-in synthesis. We have investigated both structural and biochemical features of shelterin and CST complexes to get a clear understanding of their importance in the telomere maintenance. Further, we have analyzed ~115 clinically important mutations in both of the complexes. Association of such mutations with specific cellular fault unveils the importance of shelterin and CST complexes in the maintenance of genome stability. A possibility of targeting shelterin and CST by small molecule inhibitors is further investigated towards the therapeutic management of associated diseases. Overall, this review provides a possible direction to understand the mechanisms of telomere borne diseases, and their therapeutic intervention.</jats:p