Evaluation of the Function of Probiotics, Emphasizing the Role of their Binding to the Intestinal Epithelium in the Stability and their Effects on the Immune System.

Due to the importance of using cost-effective methods for therapeutic purposes, the function of probiotics as safe microorganisms and the study of their relevant functional mechanisms have recently been in the spotlight. Finding the mechanisms of attachment and stability and their beneficial effects on the immune system can be useful in identifying and increasing the therapeutic effects of probiotics. In this review, the functional mechanisms of probiotics were comprehensively investigated. Relevant articles were searched in scientific sources, documents, and databases, including PubMed, NCBI, Bactibace, OptiBac, and Bagel4. The most important functional mechanisms of probiotics and their effects on strengthening the epithelial barrier, competitive inhibition of pathogenic microorganisms, production of antimicrobials, binding and interaction with the host, and regulatory effects on the immune system were discussed.In this regard, the attachment of probiotics to the epithelium is very important because the prerequisite for their proper functioning is to establish a proper connection to the epithelium. Therefore, more attention should be paid to the binding effect of probiotics, including sortase A, a significant factor involved in the expression of sortase-dependent proteins (SDP), on their surface as mediators of intestinal epithelial cell binding. In general, by investigating the functional mechanisms of probiotics, it was concluded that the mechanism by which probiotics regulate the immune system and adhesion capacity can directly and indirectly have preventive and therapeutic effects on a wide range of diseases. However, further study of these mechanisms requires extensive research on various aspects.

Identification of a novel heterozygous mutation in the MITF gene in an Iranian family with Waardenburg syndrome type II using next-generation sequencing.

BACKGROUND: Waardenburg syndrome (WS) is a genetically heterogeneous syndrome with both autosomal recessive and dominant inheritance. WS causes skin and iris pigmentation accumulation and sensorineural hearing loss, in varying degrees. There are four WS types with different characteristics. WS1 and WS2 are the most common and have a dominant inheritance. WS2 is caused by mutations in the microphthalmia-associated transcription factor (MITF) gene. METHODS: An Iranian couple with hearing loss was recruited in the present study. First, they were screened for GJB2 and GJB6 gene mutations, and then whole-exome sequencing 100X was performed along with bioinformatics analysis. RESULTS: A novel pathogenic heterozygous mutation, c.425T>A; p.L142Ter, was detected in the MITF gene's exon 4. Bioinformatics analysis predicted c.425T>A; p.L142Ter as a possible pathogenic variation. It appears that the mutated transcript level declines through nonsense-mediated decay. It probably created a significantly truncated protein and lost conserved and functional domains like basic helix-loop-helix-zipper proteins. Besides, the variant was utterly co-segregated with the disease within the family. CONCLUSIONS: We investigated an Iranian family with congenital hearing loss and identified a novel pathogenic variant c.425T>A; p. L142Ter in the MITF gene related to WS2. This variant is a nonsense mutation, probably leading to a premature stop codon. Our data may be beneficial in upgrading gene mutation databases and identifying WS2 causes.

Green synthesis of metal nanoparticles using microorganisms and their application in the agrifood sector.

The agricultural sector is currently facing many global challenges, such as climate change, and environmental problems such as the release of pesticides and fertilizers, which will be exacerbated in the face of population growth and food shortages. Therefore, the need to change traditional farming methods and replace them with new technologies is essential, and the application of nanotechnology, especially green technology offers considerable promise in alleviating these problems. Nanotechnology has led to changes and advances in many technologies and has the potential to transform various fields of the agricultural sector, including biosensors, pesticides, fertilizers, food packaging and other areas of the agricultural industry. Due to their unique properties, nanomaterials are considered as suitable carriers for stabilizing fertilizers and pesticides, as well as facilitating controlled nutrient transfer and increasing crop protection. The production of nanoparticles by physical and chemical methods requires the use of hazardous materials, advanced equipment, and has a negative impact on the environment. Thus, over the last decade, research activities in the context of nanotechnology have shifted towards environmentally friendly and economically viable 'green' synthesis to support the increasing use of nanoparticles in various industries. Green synthesis, as part of bio-inspired protocols, provides reliable and sustainable methods for the biosynthesis of nanoparticles by a wide range of microorganisms rather than current synthetic processes. Therefore, this field is developing rapidly and new methods in this field are constantly being invented to improve the properties of nanoparticles. In this review, we consider the latest advances and innovations in the production of metal nanoparticles using green synthesis by different groups of microorganisms and the application of these nanoparticles in various agricultural sectors to achieve food security, improve crop production and reduce the use of pesticides. In addition, the mechanism of synthesis of metal nanoparticles by different microorganisms and their advantages and disadvantages compared to other common methods are presented.