Current Protein and Peptide Science - Volume 24, Issue 2, 2023

Background: Highly evolved biocatalysts that can endure harsh environmental conditions during industrial processes are highly desirable. The availability of suitable biocatalysts with high enzyme activity, substrate selectivity, and stability could lower the production costs in the pharmaceutical, chemical, and food industries, resulting in more economical products. Objectives: Naturally evolved enzymes could not be exploited in industrial applications because of their compromised properties. Till date, protein engineering strategies have helped us to improve the desired physical and catalytic properties of enzymes to meet their performance needs in industrial and medical applications. Results: Protein engineering technologies such as directed evolution and rational designing are wellsuited for improving biocatalytic properties. Each approach has its own set of limitations, and the implementation of techniques is contingent on the availability of prerequisite information about the biocatalyst. Protein structure information is essential for rational design, but no prior structural knowledge is required for directed evolution. Furthermore, semi-rational approaches and enzyme designing are also being used. Considering these facts, this study outlines the various molecular techniques used to improve the physical and catalytic properties of enzymes. It also emphasises the magnitude of strategies used to improve the properties of biocatalysts to meet the needs of industrial processes. Conclusion: Protein engineering frequently employs for improving crucial enzyme characteristics. A semi-rational approach has now emerged as the preferred technology for protein engineering. However, adopting an engineering strategy to achieve the desired characteristic depends on the availability of resources and subject-matter knowledge.

Background: With the advent of cancer diagnostics and therapeutics, circular RNAs (circRNAs) are swiftly becoming one of the significant regulators of gene expression and cellular functions. A plethora of multiple molecular mechanisms has been observed to elicit their influence. Objective: Circular RNAs (circRNAs) are a distinct category of endogenous noncoding RNAs designed as a result of exon back splicing events in precursor’s mRNAs (pre-mRNAs) and are widely distributed in the transcriptome of eukaryotic cells. Methods: Although the role of circRNAs is still in its infancy, they serve as microRNA sponges, protein scaffolds, and modulators of transcription and splicing and occasionally as templates for the production of peptides. Results: It is well known that abnormal circRNA expression is prevalent in malignancies and has been linked to a number of pathophysiological aspects of cancer. This extensively anomalous expression assists in cellular proliferation and growth, sustaining cellular invasiveness and bypassing cellular senescence and death, thus advocating their promise to serve as both clinical biomarkers and therapeutic targets. Conclusion: An overview of the recent status of circRNA will aid in the identification of new biomarkers, therapeutic targets, and their prospect in the diagnosis and therapy of disease. In this review article, we discuss the functional mechanisms of circRNAs, their biomarker potential in disease diagnosis and prognosis, therapeutic approaches, and the associated limitations.

Nerve injuries and lesions often lead to the loss of neural control, reducing the patients’ quality of lives. Nerve self-repair is difficult due to the low regeneration capacity, insufficient secretion of neurotrophic factors, secondary complications, and adverse microenvironmental conditions such as severe hypoxia-ischemia, inflammation, and oxidative stress. Effective therapies that can accelerate nerve regeneration have been explored. Cytokine therapy can significantly improve neural survival and myelin regeneration during nerve repair. Insulin-like growth factor-1 (IGF-1) and its isoforms (IGF- 1Ea and IGF-1Eb/Ec [also known as MGF]) represent a promising therapeutic approach regarding nerve repair, given their well-described proliferative and anti-apoptotic capacities on neurons withstanding the adverse environmental conditions. This review summarizes the research progress regarding the effects of IGF-1 and its isoforms on nerve repair after nerve injury, hypoxic-ischemic insult, inflammation, and oxidative stress. We provide a theoretical basis for the clinical treatment of nerve injuries.

Background: Multidrug-resistant (MDR) methicillin-resistant Staphylococcus aureus (MRSA) has become a prime health concern globally. These bacteria are found in hospital areas where they are regularly dealing with antibiotics. This brings many possibilities for its mutation, so drug resistance occurs. Introduction: Nowadays, these nosocomial MRSA strains spread into the community and live stocks. Resistance in Staphylococcus aureus is due to mutations in their genetic elements. Methods: As the bacteria become resistant to antibiotics, new approaches like antimicrobial peptides (AMPs) play a vital role and are more efficacious, economical, time, and energy saviours. Results: Machine learning approaches of Artificial Intelligence are the in silico technique which has their importance in better prediction, analysis, and fetching of important details regarding AMPs. Conclusion: Anti-microbial peptides could be the next-generation solution to combat drug resistance among Superbugs. For better prediction and analysis, implementing the in silico technique is beneficial for fast and more accurate results.

Background: p21-activated kinase 1 (PAK1) is abnormally expressed in glioma, but its roles and mechanisms in glioma remain unclear. This study aims to explore the effects of PAK1 inhibition on the proliferation, migration and invasion of glioma cells. Methods: Cell Counting Kit-8 (CCK-8), 5128;ethynyl128;20128;deoxyuridine (EdU) incorporation and colony formation assays were performed to evaluate the effects of PAK1 inhibition on the proliferation of glioma cells. The cell cycle distribution and apoptosis rate of glioma cells were explored by flow cytometry. Wound healing and Transwell assays were performed to investigate the effects of PAK1 inhibition on glioma cell migration and invasion. The orthotopic xenograft glioma model was used to probe the effect of PAK1 silencing on glioma tumor formation. Results: PAK1 inhibition arrested cells at the G1 phase and induced apoptosis of glioma cells. Moreover, the knockdown of PAK1 decreased the protein expression levels of MDM2, p38, p-p38, cyclin D1, CDK4, Bcl-2, MMP2, MMP9, and cofilin but increased the protein levels of p53, Bax, p21 and cleaved caspase-3. A xenograft glioma model confirmed that the silencing of PAK1 repressed the formation of tumors induced by U87 cell transplantation. Conclusion: This study showed that PAK1 inhibition impedes the proliferation, migration, and invasion of glioma cells.

Background: Metastasis is the major cause of treatment failure in cancer patients and cancer- associated death, and an antimetastatic drug would be a beneficial therapy for cancer patients. HM-3-HSA is a fusion protein which improved the pharmacokinetics of HM-3 and exerted antitumor and anti-angiogenesis activity in multiple tumor models. However, the efficacy of HM-3-HSA in cancer cell migration and metastasis has not been elucidated. Materials and Methods: Herein, high-cell density fermentation of Pichiapink strain expressing HM- 3-HSA was performed for the first time. Then, the desired protein was purified by Butyl Sepharose High performance, Capto Blue, Phenyl Sepharose 6FF HS and DEAE Sepharose FF. Furthermore, the effect of HM-3-HSA on the migration and invasion of cancer cells was also evaluated, and B16F10 metastasis model was established to detected the anti- metastasis effect of HM-3-HSA in vivo. Results: The results indicated that the yield of HM-3-HSA was 320 mg/L in a 10 L fermenter, which was a 46% increase over that expressed in flask cultivation. The desired protein was purified by fourstep, which yielded a 40% recovery of a product that had over 99% purity. Purified HM-3-HSA significantly suppressed the migration and invasion of HCT-116, SMMC-7721 and B16F10 cell lines. Conclusion: On the other hand, in the B16F10 metastasis model, HM-3-HSA significantly inhibited pulmonary metastases of B16F10 cells, suggesting that HM-3-HSA exerted the anti-metastasis effect in vivo.