ß-Galactosidase: From its source and applications to its recombinant form.

Carbohydrate-active enzymes are a group of important enzymes playing a critical role in the degradation and synthesis of carbohydrates. Glycosidases can hydrolyze glycosides into oligosaccharides, polysaccharides, and glycoconjugates via a cost-effective approach. Lactase is an important member of ß-glycosidases found in higher plants, animals, and microorganisms. ß-Galactosidases can be used to degrade the milk lactose for making lactose-free milk, which is sweeter than regular milk and is suitable for lactose-intolerant people. ß-Galactosidase is employed by many food industries to degrade lactose and improve the digestibility, sweetness, solubility, and flavor of dairy products. ß-Galactosidase enzymes have various families and are applied in the food-processing industries such as hydrolyzed-milk products, whey, and galactooligosaccharides. Thus, this enzyme is a valuable protein which is now produced by recombinant technology. In this review, origins, structure, recombinant production, and critical modifications of ß-galactosidase for improving the production process are discussed. Since ß-galactosidase is a valuable enzyme in industry and health care, a study of its various aspects is important in industrial biotechnology and applied biochemistry.

Patients with Covid 19 have significantly reduced CH50 activity.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes coronavirus disease 2019 (COVID-19), is a new virus that emerged in China and immediately spread around the world. Evidence has been documented that the immune system is impressively involved in the pathogenesis of this disease, especially in causing inflammation. One of the important components of the immune system is the complement system whose increased activity has been shown in inflammatory diseases and consequently damage caused by the activity of its components. In the present study, serum levels of C3 and C4 factors as well as the activity level of complement system in the classical pathway were measured by CH50 test in patients with SARS-CoV-2. Participants in the study consisted of 53 hospitalized patients whose real-time PCR test was positive for SARS-CoV-2. The mean age of these patients was 42.06 ± 18.7 years, including 40% women and 60% men. The most common symptoms in these patients were cough (70%), fever (59%), dyspnea (53%) and chills (53%), respectively. Analysis of biochemical and hematological test results revealed that 26 (49%) patients had lymphopenia, 34 (64%) patients were positive for C-reactive protein (CRP) and 26 (49%) patients had ESR and LDH levels significantly higher than normal. In addition, 27 patients (51%) had vitamin D deficiency. The mean CH50 activity level in COVID-19 patients was significantly reduced compared to healthy individuals (84.9 versus 169.9 U/ml, p = < 0.0001). Comparison of the mean CH50 activity levels between different subgroups of patients indicated that COVID-19 patients with decreased peripheral blood lymphocyte count and positive CRP had a significant increase in activity compared to the other groups (p = 0.0002). The serum levels of C3 and C4 factors had no significant change between patients and healthy individuals. Conclusion: The activity level of complement system in the classical pathway decreases in COVID-19 patients compared to healthy individuals, due to increased activity of complement system factors in these patients.

Bispecific antibodies in colorectal cancer therapy: recent insights and emerging concepts.

Colorectal cancer (CRC) is identified as a life-threatening malignancy. Despite several efforts and proceedings available for CRC therapy, it is still a health concern. Among a vast array of novel therapeutic procedures, employing bispecific antibodies (BsAbs) is currently considered to be a promising approach for cancer therapy. BsAbs, as a large family of molecules designed to realize two distinct epitopes or antigens, can be beneficial microgadgets to target the tumor-associated antigen pairs. On the other hand, applying the immune system's capabilities to attack malignant cells has been proven as a tremendous development in cancer therapeutic projects. The current study has attempted to overview some of the approved BsAbs in CRC therapy and those under clinical trials. For this purpose, reputable scientific search engines and databases, such as PubMed, ScienceDirect, Google Scholar, Scopus, etc., were explored using the keywords 'bispecific antibodies', 'colorectal cancer', 'immunotherapy' and 'tumor markers'.

Antibacterial activity of honeys and potential synergism of honeys with antibiotics and alkaloid extract of Sophora alopecuroides plant against antibiotic-resistant Escherichia coli mutant.

OBJECTIVES: The increase in multidrug-resistant Escherichia coli strains with an overactivated AcrAB-TolC efflux pump has reduced the effectiveness of synthetic antibiotics, such as ciprofloxacin. The activity of this efflux pump can be reduced by using natural products. This study aimed to use a combination of ciprofloxacin, honey, and alkaloid extract of Sophora alopecuroides against an E. coli mutant with an overactivated AcrAB-TolC pump. MATERIALS AND METHODS: First the physicochemical properties, total alkaloid content, antioxidant activity, and the minimum inhibitory concentration (MIC) of three local honey samples: Konar (lotus), Avishan (Thyme), and Gavan (Astragalus) were evaluated. Then, the MIC of different combinations of honey, ciprofloxacin, and plant alkaloid extract and expression of acrA and soxS genes were carried out using the agar dilution method and quantitative RT- PCR methods. RESULTS: The net absorbance, total alkaloid content, and DPPH radical scavenging activity of Konar honey were significantly higher than those of Avishan and Gavan honeys (P<0.05). However, the MIC of lotus honey was nearly similar to other honey types, and all honey (30% w/v)-ciprofloxacin combinations decreased the viability of mutant more than ciprofloxacin alone. A synergistic interaction (FICI =0.48) was observed in triplex complex of ciprofloxacin (10 µg/ml), honey (20% w/v), and plant extract (1 mg/ml). A significant decrease (P<0.05) in the expression level of genes was seen in the presence of the triplex complex. CONCLUSION: It is concluded that the interaction between honey and plant alkaloid extract enhanced the anti-pump activity and reduced the oxidative stress response of the E. coli mutant.

Designing of a Novel Fusion Protein Vaccine Candidate Against Human Visceral Leishmaniasis (VL) Using Immunoinformatics and Structural Approaches.

Leishmaniasis is caused by an obligate intracellular protozoan parasite. The clinical forms of leishmaniasis differ from cutaneous leishmaniasis, mucocutaneous leishmaniasis and visceral leishmaniasis (VL) which depend on the parasite species and the host's immune responses. There are significant challenges to the available anti-leishmanial drug therapy, particularly in severe forms of disease, and the rise of drug resistance has made it more difficult. Currently, no licensed vaccines have been introduced to the market for the control and elimination of VL. A potential target for use in candidate vaccines against leishmaniasis has been shown to be leishmania Kinetoplastid membrane protein-11 (KMP-11) antigen. In this study, we chose KMP-11 antigen as target antigen in our vaccine construct. In addition, B-type flagellin (fliC) was used as an adjuvant for enhancing vaccine immunogenicity. The GSGSGSGSGSG linker was applied to link the KMP-11 antigen and fliC (KMP-11-fliC) to construct our fusion protein. Bioinformatics approaches such as; 3D homology modeling, CTL, B-cell, MHC class I and II epitopes prediction, allergenicity, antigenicity evaluations, molecular docking, fast simulations of flexibility of docked complex and in silico cloning were employed to analysis and evaluation of various properties of the designed fusion construct. Computational results showed that our engineered structure has the potential for proper stimulation of cellular and humoral immune responses against VL. Consequently, it could be proposed as a candidate vaccine against VL according to these data and after verifying the efficacy of the candidate vaccine through in vivo and in vitro immunological tests.