Current protein & peptide science最新文献

Aim: Our research aimed to isolate and sequence the SOD gene from the genomic DNA of Scylla serrata and Scylla olivacea and to study its phylogeny.

Background: In crustaceans, superoxide dismutase (SOD) serves as the first line of defense against stress. Extracellular Cu/Zn-SOD has been demonstrated in several investigations involving crustaceans. Crustaceans do not have a distinct immune system. They entirely depend on the innate immune system triggered when they come in contact with any pathogen.

Methods: Partial SOD gene was isolated from the genomic DNA of S. serrata and S. olivacea through polymerase chain reaction.

Results: We successfully isolated partial SOD genes of 942bp and 957bp from S. serrata and S. olivacea, respectively. The sequences were submitted to the NCBI GenBank database.

Discussion: The phylogenetic study suggests their clustering with the genus Scylla species. Investigating the SOD gene sequences across diverse crustacean lineages can reveal profound insights into their evolutionary history and the intricate relationships among species concerning their SOD development.

Conclusion: This research holds the potential to enhance our understanding of the evolutionary adaptations that have shaped these organisms.

COVID-19 is a respiratory disease caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), but because the receptor protein of this virus can appear not only in the lungs and throat but also in various parts of the host's body, it causes different diseases. Recent observations have suggested that SARS-CoV-2 damages the central nervous system of patients in a manner similar to amyloid-associated neurodegenerative diseases such as Alzheimer's and Parkinson's. Neurodegenerative diseases are believed to be associated with the self-assembly of amyloid proteins and peptides. On the other hand, whole proteins or parts of them encoded by SARS-CoV-2 can form amyloid fibrils, which may play an important role in amyloid-related diseases. Motivated by this evidence, this mini-review discusses experimental and computational studies of SARS-CoV-2 proteins that can form amyloid aggregates. Liquid-Liquid Phase Separation (LLPS) is a dynamic and reversible process leading to the creation of membrane-less organelles within the cytoplasm, which is not bound by a membrane that concentrates specific types of biomolecules. These organelles play pivotal roles in cellular signaling, stress response, and the regulation of biomolecular condensates. Recently, LLPS of the Nucleocapsid (N) protein and SARS-CoV-2 RNA has been disclosed, but many questions about the phase separation mechanism and the formation of the virion core are still unclear. We summarize the results of this phenomenon and suggest potentially intriguing issues for future research.

One of the most well-known instances of an interdisciplinary subject is tissue engineering, where experts from many backgrounds collaborate to address important health issues and improve people's quality of life. Many researchers are interested in using chitosan and its derivatives as an alternative to fabricating scaffold engineering and skin grafts in tissue because of its natural abundance, affordability, biodegradability, biocompatibility, and wound healing properties. Nanomaterials based on peptides can provide cells with the essential biological cues required to promote cellular adhesion and are easily fabricated. Due to such worthy properties of chitosan and peptide, they find their application in tissue engineering and regeneration processes. The implementation of hybrids of chitosan and peptide is increasing in the field of tissue engineering and scaffolding for improved cellular adherence and bioactivity. This review covers the individual applications of peptide and chitosan in tissue engineering and further discusses the role of their conjugates in the same. Here, the recent findings are also discussed, along with studies involving the use of these hybrids in tissue engineering applications.

Human paraoxonase 1 (hPON1) is a Ca2+-dependent metalloenzyme with multifunctional properties. Due to its diverse activities (arylesterase, phosphotriesterase, and lactonase), it plays a significant role in disease conditions. Researchers across the globe have demonstrated different properties of PON1, like anti-oxidant, anti-inflammatory, anti-atherogenic, anti-diabetic, and OPneutralization. Due to its pleotropic role in disease conditions like atherosclerosis, diabetes, cardiovascular diseases, neurodegenerative disorders, and OP-poisoning, it can be considered as a potential candidate for the development of therapeutic interventions. Attempts are being made in this direction to identify the exact role of PON1 in these disease conditions. Different approaches like directed evolution, genetic as well as chemical fusion, liposomal delivery of PON1, etc., are being developed and evaluated for their therapeutic effects in different pathological conditions. In this review, we outline the exact role and involvement of different properties of PON1 in the pathophysiology of different diseases and how it can be utilized and developed as a therapeutic intervention in PON1-associated disease conditions.

Background: Cathepsin D is a lysosomal enzyme that plays a critical role in the process of protein catabolism. In marine organisms, research has primarily concentrated on the identification of the enzyme. However, in crustaceans and molluscs, it is known to have digestive functions, as it is the sole enzyme responsible for protein degradation at extremely acidic pH in the hepatopancreas. In the Japanese clam (Ruditapes philippinarum), cathepsin D was purified and partially characterised from the hepatopancreas.

Methods: To evaluate changes in secondary structure, circular dichroism (CD) was employed under a range of 5-70°C and pH of 1-7.5. Following dissection, the enzyme was purified from the hepatopancreas by ultrafiltration and affinity chromatography. SDS-PAGE was used to verify the sample purity, and gel filtration was used to determine the molecular weight. CD spectra were obtained at a concentration of 0.125 mg/mL, expressed as mean ellipticity per residue.

Results: The purified cathepsin D demonstrated a specific activity of 5,553 ± 220 U/mg and a molecular weight of 36.5 kDa. The enzyme demonstrated optimal activity within a temperature range of 45-50°C and a pH range of 3-3.5. CD analyses demonstrated alterations in the secondary structure at elevated temperatures and pH fluctuations, which were correlated with a reduction in enzyme activity.

Conclusion: cathepsin D from R. philippinarum exhibited high thermostability up to 50°C and activity at pH 2-4. Its stability and characteristics are comparable to those of other species, which opens avenues in biotechnology for protein hydrolysis and peptide production.

Objectives: The aim of this study was to investigate the expression characteristics and interrelationships of FNDC5 and pyroptosis-associated molecules in peripheral blood mononuclear cells of patients with coronary heart disease (CHD).

Methods: Patients were divided into stable angina (SA), unstable angina (UA), and acute myocardial infarction (AMI) groups based on different clinical symptoms. According to the Gensini score, they were then divided into mild, moderate, and severe lesion groups. The control (NC) group was also set. ELISA assay was employed to detect the levels of Irisin, IL-1β, and IL-18, and the levels of pyroptosis-associated molecules, NF-κB p50, NF-κB p65, and FNDC5 were detected and compared by qRT-PCR and Western blot (WB). Logistic regression and Spearman's partial correlation analysis were used to analyze the pathogenic factors of CHD and explore the interrelationships between FNDC5 and the molecules.

Results: IL-1β and IL-18 of CHD patients were increased, while the Irisin was decreased. With the aggravation of symptoms and severity of coronary artery stenosis, the former increased, and the Irisin gradually decreased (P<0.05). About qRT-PCR and WB: With the aggravation of symptoms, the levels of pyroptosis-associated molecules and other indicators were increased, and FNDC5 was decreased (Pπ0.05). NLRP3, Caspase-1, and NF-κB p50 protein were positively correlated with the incidence of CHD, and FNDC5 was also negatively correlated with that of CHD. Even when common risk factors for CHD were taken into account, FNDC5 and NLRP3 were still found to be negatively connected.

Conclusion: The decreased expression level of FNDC5 and the increased level of pyroptosis-associated molecules may be related to CHD.

The three-dimensional structure of proteins, achieved through the folding of the nascent polypeptide chain in vivo, is largely facilitated by molecular chaperones, which are crucial for determining protein functionality. In addition to aiding in the folding process, chaperones target misfolded proteins for degradation, acting as a quality control system within the cell. Defective protein folding has been implicated in a wide range of clinical conditions, including neurodegenerative and metabolic disorders. It is now well understood that the pathogenesis of neurodegenerative diseases such as Parkinson's disease, Alzheimer's disease, Huntington's disease, Amyotrophic Lateral Sclerosis, and Creutzfeldt-Jakob disease shares a common mechanism: the accumulation of misfolded proteins, which aggregate and become toxic to cells. Among the family of molecular chaperones, Heat Shock Proteins (HSPs) are highly expressed in response to cellular stress and play a pivotal role in preventing protein aggregation. Specific chaperones, particularly HSPs, are now recognized as critical in halting the accumulation and aggregation of misfolded proteins in these conditions. Consequently, these chaperones are increasingly considered promising pharmacological targets for the treatment of protein aggregation-related diseases. This review highlights research exploring the potential roles of specific molecular chaperones in disorders characterized by the accumulation of misfolded proteins.

Objective: Eating insects may be healthier and more sustainable than eating animals. Various insect protein hydrolysates are assessed for therapeutic potential in this review.

Methods: A wide range of literature pertaining to nutrition compositions and the biological activity of edible insects has been compiled and meticulously examined through the utilization of various scholarly databases, including PubMed and ScienceDirect.

Results: Different insect protein hydrolysates had anti-inflammatory, anti-cancer, and antioxidant characteristics in addition to controlling blood sugar and cholesterol. These findings suggest that insect-derived bioactive peptides have health benefits and therapeutic uses.

Conclusion: Edible insects may replace traditional foods due to their nutritional and environmental benefits. The biological activity of their protein hydrolysates suggests they could be beneficial food additives or medicines.

Introduction: Membraneless organelles, such as nucleoli, stress granules, and P-bodies, are not enclosed by lipid membranes; rather, they are formed through a process known as liquid-liquid phase separation. To fully understand the biophysics behind the formation and regulation of these organelles, knowledge that has significant implications for cellular biology and disease research, the creation of phase diagrams is essential. Phase diagrams help clarify the physical and chemical conditions under which these organelles form, exist, and function within cells. However, methods for creating phase diagrams are often limited when the equation of state is unknown, a challenge that becomes more pronounced with increasing system complexity. While several methods exist to address this issue, their application is not universal.

Methods: We present a new method based on the SPACEBALL algorithm and cluster size monitoring, which enables the determination of binodal and spinodal line positions by analyzing system clustering during molecular dynamics simulations of a well-studied van der Waals fluid under various conditions.

Results: Based on an analysis of the system's clustering behavior, we constructed the phase diagram for the monoatomic van der Waals fluid simulated at various densities and temperatures, observing that uniformly distributed van der Waals beads aggregate, causing changes in the system's density.

Discussion: Using the generated data, we discuss how a fitting function can be used to determine the binodal line location, and how observations of the system's density fluctuations can be used to determine the spinodal line location and assess the critical temperature.

Conclusion: We have presented alternative methods for locating phase boundaries in protein solutions, where the absence of a validated equation of state necessitates innovative approaches and makes traditional methods challenging to apply. Our SPACEBALL-based approach enables the creation of phase diagrams using pure trajectories obtained from molecular dynamics simulations.