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AbstractPeptide-based medications hold immense potential in addressing a wide range of human disorders and discomforts. However, their widespread utilization encounters two major challenges: preservation and production efficiency. Cyclotides, a class of ribosomally synthesized and post-translationally modified peptides (RiPPs), exhibit unique characteristics, such as a cyclic backbone and cystine knot, enhancing their stability and contributing to a wide range of pharmacological properties exhibited by these compounds. Cyclotides are efficient in the biomedical (e.g., antitumor, antidiabetic, antimicrobial, antiviral) and agrochemical fields by exhibiting activity against pests and plant diseases. Furthermore, their structural attributes make them suitable as molecular scaffolds for grafting and drug delivery. Notably, the mutated variant of kalata B1 cyclotide ([T20K] kalata B1) has recently entered phase 1 of human clinical trials for multiple sclerosis, building upon the success observed in animal trials. To enable large-scale production of cyclotides, it is crucial to further explore their remarkable structural and bioactive properties. This necessitates extensive research focused on enhancing the efficiency of the processes required for their production. This study provides a comprehensive review of the biological synthesis methods of cyclotides, with particular emphasis on various expression systems, namely bacteria, plants, yeast, and cell-free systems. By investigating these expression systems, it becomes possible to design production systems that are adaptable, economically viable, and efficient for generating active and pure cyclotides at an industrial scale. The advantages of biological synthesis over chemical synthesis are thoroughly explored, highlighting the potential of these expression systems in meeting the demands of large-scale cyclotide production. [ABSTRACT FROM AUTHOR]

Since teachers’ perceptions of work engagement can strongly shape their engagement level, it is imperative to explore how teachers perceive this construct and its associated dimensions. With this in mind, some researchers have evaluated teachers’ beliefs and attitudes towards this notion. Notwithstanding this, to the authors’ knowledge, no study has examined language teachers’ viewpoints on this variable and its significance in online EFL classes. To bridge these gaps, this phenomenological study explored Iranian EFL teachers’ perceptions and experiences of work engagement and its value in online English courses. To this aim, using the purposive sampling strategy, a total of 21 EFL teachers were chosen from different state, private, and non-profit universities in Iran. To obtain the required data, all participants were invited to complete an open- ended questionnaire. To reach more comprehensive data, from among the 21 participants, nine willingly took part in a 20-minute interview session. Results obtained from content analysis revealed that Iranian EFL teachers considered work engagement as a complex variable with four related dimensions of emotional, cognitive, behavioral, and social engagement. The results also indicated that Iranian teachers perceived work engagement as an important professional behavior that results in increased academic achievements, professional advancement, improved teaching quality, and strong teacher-student rapport. Hence, education leaders and teacher educators should support Iranian EFL teachers in enhancing work engagement dimensions to improve professional growth and teaching quality. [ABSTRACT FROM AUTHOR]

Cecropin A, as an antimicrobial peptide (AMP), is possible to use in medical and agricultural fields as a new and safe biocontrol agent. Therefore, it is highly necessary to find a cost‐effective and scalable approach to generate a large scale of it. In this research, the Agrobacterium rhizogenes strain ATCC 15834 was used to transfer the Cecropin A gene to the Nicotiana tabacum. After confirmation of transgenic hairy roots, the antibacterial activity of purified Cecropin A peptide was measured using the agar gel diffusion method. Successful transforming of Cecropin A was confirmed at the RNA and protein levels in hairy root cells using RT‐PCR and enzyme‐linked immunosorbent assay (ELISA), respectively. The highest Cecropin A amount was detected in line 4 of the transgenic lines using ELISA in comparison with the nontransgenic line. Subsequently, the antimicrobial activity of Cecropin A extracted from line 4 showed the highest inhibition activity against Aspergillus niger. Besides, this activity was stable against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Candida albicans pathogens after 7 days. The recombinant production of Cecropin A AMP had a yield of 63.81 μg/g of fresh weight. According to a significant yield, this system can be used to produce the Cecropin A peptide for pharmacological and food science applications. [ABSTRACT FROM AUTHOR]