The snake venom is a potent source of a variety of drugs and therapeutic components. This study aimed to isolate and characterize some of proteins in Montivipera raddei venom. The protein bands and spots obtained by SDS-PAGE and two-dimensional electrophoresis were analyzed. The separated protein spots based on isoelectric point and molecular weight were scattered in the 15 to 66 kDa ranges and pI from 5 to 8. Six proteins was more extensively characterized by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF/TOF) analysis. These characterized proteins included Zinc metalloproteinase-disintegrin-like ecarin, L-amino-acid oxidase, metalloproteinase kistomin, Thiamine-monophosphate kinase, Ancrod, Acidic phospholipase A2.

HIGHLIGHTS

• Identification of several proteins from Montivipera raddei venom.
• Characterization of the six high concentrated proteins by MALDI-TOF/TOF spectroscopy in venom.
• Zinc metalloproteinase-disintegrin-like ecarin, L-amino-acid oxidase, metalloproteinase kistomin, Thiamine-monophosphate kinase, Ancrod, Acidic phospholipase A2 were identified in venom of Montivipera raddei.

Luciferase is a well-known oxidative enzyme that produces bioluminescence. The Pseudomonas meliae is a plant pathogen that causes wood to rot on nectarine and peach and possesses a luciferase-like monooxygenase. After activation, it produces bioluminescence, and the pathogen’s bioluminescence is a visual indicator of contaminated plants. The present study aims to model and characterize the luciferase-like monooxygenase protein in P. meliae for its similarity to well-established luciferase. In this study, the luciferase-like monooxygenase from P. meliae infects chinaberry plants has been first modeled and then, studied by comparing it with existing known luciferase. In addition, the similarities between uncharacterized luciferase from P. meliae and the template from Geobacillus thermodenitrificans were analyzed. The results suggest that the absence of bioluminescence in P. meliae could be critical for the production of the luciferin substrate and the catalytic activity of the enzyme due to the evolutionary mutation in positions 138 and 311. The active site remains identical except for two amino acids. Therefore, mutation of the residues 138 and 311 in P. meliae Luciferase-like monooxygenase may restore luciferase light-emitting ability.

HIGHLIGHTS

• Structural characterization of luciferase-like monooxygenase in P. meliae.
• Bioluminescence can be used to evaluate antimicrobial efficacy by releasing light emissions.
• Luciferase-like monooxygenase: a potential therapeutic candidate for clinical applications.

Mumijo is a traditional drug that has been used in traditional medicine for a long time and its aqueous extract is used for the treatment of osteoporosis and bone fractures. Besides, in modern medicine, nano-sized hydroxyapatite (nHA) has achieved immense attention for bone integration and regeneration of bony defects treatment. Since the frequency of accidental bone disorders and damage is growing worldwide, the need for artificial bone implants is increasing. Thus, in this study, the fibrillar beta-lactoglobulin (BLG)-Mumijo-nHA complex was synthesized and characterized by UV–Visible, fluorescence, Fourier transform infrared, circular dichroism spectroscopy, scanning electron microscopy, and zeta potential analysis. The results showed that the fibrillar BLG-Mumijo-nHA complex was formed. The results also confirmed that the complex had a negative surface charge and was moderately stable. Cell viability assays indicated that fibrillar BLG-Mumijo-nHA complex induced bone marrow-derived mesenchymal stem cell growth at higher concentrations. Although further experiments are warranted to draw firm conclusions, it could be proposed that the fibrillar BLG-Mumijo-nHA complex could be a good candidate for the treatment of osteoporosis and bone fractures.

Highlights

• The fibrillar BLG-Mumijo-nHA complex was synthesized in detail.
• UV-Visible, fluorescence emission, and CD spectroscopy as well as z-potential value confirmed the formation of a complex.
• The complex could be a good candidate for tissue engineering.

The Programmed cell death ligand-1 (PD-L1), an immune checkpoint molecule, is the ligand of Programmed cell death protein 1 (PD-1). They are crucial molecules in maintaining immune homeostasis. PD-L1/PD-1 axis regulates the initiation and maintenance of tolerance and protects tissues from autoimmune responses; however, cancer cells can use the PD-1/PD-1 axis to evade the anti-tumor response of immune cells. Increased PD-L1 expression is directly associated with poor prognosis in hepatocellular carcinoma (HCC). Although immunotherapy with immune checkpoint inhibitors (ICIs) are leading therapy in cancer treatment, using biomarkers to regulate immune checkpoints at the RNA level is considered a promising tool in novel therapeutic approaches. Increasing evidence has reported that miRNAs are critical regulators of tumor development. Hence, we performed a current systematic review to explore PD-L1 inhibiting miRNAs involved in hepatocellular carcinoma. Five databases were systemically searched to obtain the relevant original articles. Consequently, seventeen studies were included in the current systematic review. According to obtained literatures, some microRNAs, namely miR-194-5p, -675-5p, 194-5p, -1, -455-5p, -223-3p, -513, -195, -506, -329-3p, -424, -411-5p, -182-5p, -200, -378a-3p, -570, -200c, and -513a-5p can inhibit PD-L1 expression in HCC cells. These can ultimately reduce tumor proliferation, inhibit tumor migration, stimulate the chemosensitivity of cancer cells, and induce apoptosis in tumor cells. Moreover, the investigated miRNAs were further analyzed using miRNA target prediction online tools to highlight the future direction of their functions in HCC.

HIGHLIGHTS

• Cancer cells can use the PD-1/PD-1 axis to evade the anti-tumor response of immune cells.
• Increased PD-L1 expression is directly associated with poor prognosis in hepatocellular carcinoma.
• Several microRNAscan inhibit PD-L1 expression in HCC cells.