Current Protein and Peptide Science - Volume 22, Issue 11, 2021

Plants modulate the metabolism of phytohormones and their signaling pathways under drought to regulate physiological and adaptive responses. Jasmonic acid (JA) is one of the major classes of phytohormones and has been found to potentially enhance plant tolerance to various abiotic stresses, including drought. The JASMONATE ZINC FINGER INFLORESCENCE MERISTEM (ZIM)-DOMAIN (JAZ) proteins are the negative regulators in the JA-signaling pathway. The JAZ protein family is explicit to plants and involved in the regulation of numerous biological processes, including drought-responsive mechanisms. In this review, we synthesize the mechanistic insight into the roles of JAZ proteins in the regulation of drought responses by connecting the JA-signaling with abscisic acid-signaling.

α-lipoic Acid (ALA), also known as thioctic acid, is a biological thiol present in all types of prokaryotic and eukaryotic cells. It has been shown that ALA or its reduced form, DHLA, has several positive effects on human health, acting as a biological antioxidant, metal chelator and detoxifying agent. It is able to reduce the oxidation of several antioxidant agents like glutathione, vitamins C and E, and modulate insulin and NF-kB signaling pathways. ALA’s pharmacological effects are not only related to its antioxidant properties but it shows an anti-inflammatory action. In particular, ALA is able to reduce inflammasome activity, the pro-inflammatory cytokine levels, such as TNF-α, IL-1β, IL-6, IL-18 and IL-17, interferon (INF)-γ as well as the production of Vascular and Intercellular cell adhesion protein (VCAM-1 and ICAM-1). In recent papers, ALA has been indicated as a possible therapeutic approach to several endocrine or inflammatory disorders affecting female reproduction. Aim of the current review was to assess whether ALA has an evidence- based beneficial role on gynecological and obstetrical diseases such as polycystic ovary syndrome (PCOS), endometriosis, and miscarriage.

A number of disorders and diseases are associated with conditions of high pH, and many conventional antibiotics lose their efficacy under these pH conditions, generating a need for novel antimicrobials. A potential solution to fulfill this need is Antimicrobial Peptides (AMPs) with high pH optima. This review shows that a variety of anionic and cationic AMPs with this pH dependency are produced by creatures across the eukaryotic kingdom, including rabbits, cattle, sheep, fish, crabs and frog. These AMPs exhibit activity against viruses, bacteria, and fungi that involve membrane interactions and appear to be facilitated by a variety of mechanisms that generally promote passage across membranes to attack intracellular targets, such as DNA or protein synthesisand/or membrane lysis. Some of these mechanisms are unknown, but those elucidated include the use of bacterial pores and transporters, the self-promoted uptake pathway, and established models of membrane interaction, such as the carpet mechanism, toroidal pore formation, the adoption of tilted peptide, and the SHM model. A variety of potential roles have been proposed for these AMPs, including use as antivirals, antibacterials, antifungals, adjuvants to antimicrobial therapy, biomarkers of disease, and probes for pathogenic microbes. In this review, these properties are described and discussed, emphasizing the antimicrobial mechanisms used by these AMPs and the pH dependency of these mechanisms.

Background: Proteins are biomolecules that consist of sequences of amino acids (primary structure) which can further interact and cause the backbone to fold into more complex arrangements (secondary and tertiary structures). Any chemical alterations of the molecules after the translation of the messenger RNA code into a protein primary sequence are known as posttranslational modifications (PTMs). PTMs may affect the protein’s functionality; thus it is necessary to identify them. PTMs of particular interest to the pharmaceutical industry include deamidation, oxidation, deglycosylation and isomerization, which may occur due to environmental stressors. However, they have proved challenging to identify quickly. Electronic and vibrational spectroscopies have proved valuable tools for studying higher-order structure and stability of proteins. Methods: In this work, circular dichroism (CD), infrared absorbance (IR) and Raman spectroscopies were applied to characterize antibody (mAb NIP 228) PTMs as a result of different stressors. Mass spectrometry was used to confirm the identity of modifications including the targeted ones. Results: Room temperature CD showed that the secondary structure was the same after all treatments, and temperature-controlled CD showed how protein stability was affected by modifications. Both Raman and IR analysis detected small differences between the reference and deglycosylated proteins, and clearly indicated the presence of other PTMs. Conclusion: This work required some novel computational approaches to pre-process Raman and IR spectra and a review of the band assignments for proteins existing in the literature.

Background: Salmonella enterica is the etiological agent of salmonellosis, with a high infection rate worldwide in Mexico, ST213 genotype of S. enterica ser. Typhimurium is displacing the ancestral ST19 genotype. Bacterial cytoskeleton protein complex MreBCD plays an important role in S. enterica pathogenesis, but underlying mechanisms are unknown. Results: In this study, 106 interactions among MreBCD and 15 proteins from S. Typhimurium Pathogenicity Islands 1 (SP-I) and 2 (SP-2) involved in both bacterial virulence and stress response were predicted in ST213 and ST19 genotypes, of which 12 interactions were confirmed in vitro. In addition, gene cluster analysis in 100 S. Typhimurium genomes was performed for these genes. Results and Conclusion: The in silico and in vitro results showed a novel MreBCD interactome involved in regulating pathogenesis and stress response through interactions with virulence factors located at SPI-1 and SPI-2. Furthermore, both pseudogene presence and sequence variations in four tested proteins between genotypes resulted in differential interaction patterns involved in Salmonella motility and survival in eukaryotic cells, which could explain the replacement of ST19 by ST213 in Mexico.