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Abstract The anti-cancer vinblastine and vincristine alkaloids can only be naturally found in periwinkle (Catharanthus roseus). Both of these alkaloids' accumulations are known to be influenced by salicylic acid (SA). The transcriptome data to reveal the induction effect (s) of SA, however, seem restricted at this time. In this study, the de novo approach of transcriptome assembly was performed on the RNA-Sequencing (RNA-Seq) data in C. roseus. The outcome demonstrated that SA treatment boosted the expression of all the genes in the Terpenoid Indole Alkaloids (TIAs) pathway that produces the vinblastine and vincristine alkaloids. These outcomes supported the time-course measurements of vincristine alkaloid, the end product of the TIAs pathway, and demonstrated that SA spray had a positive impact on transcription and alkaloid synthesis. Additionally, the abundance of transcription factor families including bHLH, C3H, C2H2, MYB, MYB-related, AP2/ ERF, NAC, bZIP, and WRKY suggests a role for a variety of transcription families in response to the SA stimuli. Di-nucleotide and tri-nucleotide SSRs were the most prevalent SSR markers in microsatellite analyses, making up 39% and 34% of all SSR markers, respectively, out of the 77,192 total SSRs discovered.

Satureja is rich in phenolic monoterpenoids, mainly carvacrol, that is of interest due to diverse biological activities including antifungal and antibacterial. However, limited information is available regarding the molecular mechanisms underlying carvacrol biosynthesis and its regulation for this wonderful medicinal herb. To identify the putative genes involved in carvacrol and other monoterpene biosynthesis pathway, we generated a reference transcriptome in two endemic Satureja species of Iran, containing different yields (Satureja khuzistanica and Satureja rechingeri). Cross-species differential expression analysis was conducted between two species of Satureja. 210 and 186 transcripts related to terpenoid backbone biosynthesis were identified for S. khuzistanica and S. rechingeri, respectively. 29 differentially expressed genes (DEGs) involved in terpenoid biosynthesis were identified, and these DEGs were significantly enriched in monoterpenoid biosynthesis, diterpenoid biosynthesis, sesquiterpenoid and triterpenoid biosynthesis, carotenoid biosynthesis and ubiquinone and other terpenoid-quinone biosynthesis pathways. Expression patterns of S. khuzistanica and S. rechingeri transcripts involved in the terpenoid biosynthetic pathway were evaluated. In addition, we identified 19 differentially expressed transcription factors (such as MYC4, bHLH, and ARF18) that may control terpenoid biosynthesis. We confirmed the altered expression levels of DEGs that encode carvacrol biosynthetic enzymes using quantitative real-time PCR (qRT-PCR). This study is the first report on de novo assembly and transcriptome data analysis in Satureja which could be useful for an understanding of the main constituents of Satureja essential oil and future research in this genus.

Salt stress is one of the major adverse environmental factors limiting crop productivity. Considering Iran as one of the bread wheat origins, we sequenced root transcriptome of an Iranian salt tolerant cultivar, Arg, under salt stress to extend our knowledge of the molecular basis of salinity tolerance in Triticum aestivum. RNA sequencing resulted in more than 113 million reads and about 104013 genes were obtained, among which 26171 novel transcripts were identified. A comparison of abundances showed that 5128 genes were differentially expressed due to salt stress. The differentially expressed genes (DEGs) were annotated with Gene Ontology terms, and the key pathways were identified using Kyoto Encyclopedia of Gene and Genomes (KEGG) pathway mapping. The DEGs could be classified into 227 KEGG pathways among which transporters, phenylpropanoid biosynthesis, transcription factors, glycosyltransferases, glutathione metabolism and plant hormone signal transduction represented the most significant pathways. Furthermore, the expression pattern of nine genes involved in salt stress response was compared between the salt tolerant (Arg) and susceptible (Moghan3) cultivars. A panel of novel genes and transcripts is found in this research to be differentially expressed under salinity in Arg cultivar and a model is proposed for salt stress response in this salt tolerant cultivar of wheat employing the DEGs. The achieved results can be beneficial for better understanding and improvement of salt tolerance in wheat.

Abstract This study aimed to increase the antifungal and insecticidal activities of NaD1, as an antimicrobial peptides (AMP), by improving its interaction with the fungal cell wall and chitin monomeric units in insect midguts. Hence, the chitin-binding domains (CBDs) of wheat germ agglutinin protein (WGA) were fused to either N- or C-terminus of NaD1 generating transgenic Nicotiana tabacum hairy roots (HRs). Molecular assessments confirmed the integration of NaD1 transgenes, their transcription and production of recombinant peptides in the HR lines. Total protein of (CBD) 4 -NaD1 and NaD1-(CBD) 4 transgenic lines inhibited the growth of Pyricularia oryzae mycelium, suggesting that fusion of CBD to NaD1 can increase NaD1 half-life, leading to higher affinity toward cell wall chitin. Furthermore, feeding the third-instar larvae of Chilo suppressalis with both (CBD)4-NaD1 and NaD1-(CBD)4 extracts exhibited a higher mortality rate. Both NaD1-CBDs caused a significant decrease in trypsin (TRY) and chymotrypsin (CTR) activities in the larvae, while enhancing the activity of antioxidant enzymes CAT, POD, APX, and SOD. Therefore, feeding the larvae by total extract of NaD1-(CBD)4 and (CBD)4-NaD1 HR lines probably increased affinity to midgut chitin in C. suppressalis, enhancing insecticidal activities. Overall, the results indicate that recombinant peptides are effective in enhancing fungal and insect resistance.

Potato tubers are rich sources of various nutrients and unique sources of starch. Many genes play major roles in different pathways, including carbohydrate metabolism during the potato tuber's life cycle. Despite substantial scientific evidence about the physiological and morphological development of potato tubers, the molecular genetic aspects of mechanisms underlying tuber formation have not yet been fully understood. In this study, for the first time, RNA-seq analysis was performed to shed light on the expression of genes involved in starch biosynthesis during potato tuber development. To this end, samples were collected at the hook-like stolon (Stage I), swollen tips stolon (Stage II), and tuber initiation (Stage III) stages of tuber formation. Overall, 23 GB of raw data were generated and assembled. There were more than 20000 differentially expressed genes (DEGs); the expression of 73 genes involved in starch metabolism was further studied. Moreover, qRT-PCR analysis revealed that the expression profile of the starch biosynthesis DEGs was consistent with that of the RNA-seq data, which further supported the role of the DEGs in starch biosynthesis. This study provides substantial resources on potato tuber development and several starch synthesis isoforms associated with starch biosynthesis.

Background and purpose: Rapid emergence of traditional antibiotic-resistant pathogens is one of the most important global challenges in medical sciences. To this end, substitution of current antibiotics with strong antimicrobial peptides could be of great benefit. Materials and methods: In this study, the DNA sequence encoding dermaseptin B1 (DrsB1) antimicrobial peptide derived from Phyllomedusa bicolor frog species was fused to either N or C terminal end of the sequence encoding the chitin-binding domain of the Avr4 gene from Cladosporium fulvum. The recombinant expression vectors containing two separate structures were transferred to Agrobacterium rhizogenes bacterium and then used to produce Hairy Roots (HRs) in tobacco plants. Recombinant dermaseptin B1 peptides were extracted from HRs and their antimicrobial activity was evaluated against some important human pathogens. Results: Transgene integration and expression of recombinant DrsB1 in hairy roots were confirmed by PCR and semi-quantitative RT-PCR analysis, respectively. Antimicrobial activity of the protein extracts from transgenic HRs showed that both recombinant proteins had significant inhibitory effects on the bacterial pathogens growth (P>0.01). CBD-DrsB1 recombinant protein had the highest inhibitory activity against Enterococcus faecalis and Bacillus subtilis, whereas DrsB1-CBD recombinant protein showed the least antimicrobial activity against Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa. Conclusion: To the best of our knowledge, this study for the first time showed that the new recombinant peptides possess a high antibacterial activity. Acquiring resistance to antimicrobial peptides in bacteria is not readily feasible, therefore, present findings may find application as suitable alternative for current antibiotic drugs.

Background and Aim: Enterococcus species are opportunistic pathogens and their pathogenicity seems to be related to the presence of a number of pathogenicity genes. Since donkey’s milk is a new non-allergenic source of nutrition, this study was performed to assess the antibiogram and detection of pathogenicity genes in some Enterococcus faecalis isolates from donkey’s milk. Materials and Method: In this experimental study, several Enterococcus faecalis strains were isolated from donkey’s milk. Resistance patterns of the isolates to 10 antibiotics including vancomycin were investigated based on CLSI protocol. Statistical comparison was made by Fisherchr('39')s exact test. Polymerase chain reaction (PCR) amplification was used to study gel E, esp, ace, as and efaA pathogenicity related genes. Results: Enterococcus faecalis isolates showed a different antibiogram pattern. Isolates were resistant to azithromycin, and erythromycin, but were susceptible to ampicillin and penicillin. Previously isolated LUB93929 and LUB93101 isolates were found to be susceptible and resistance to vancomycin, respectively. GelE, ace and efaA genes were detected in both Enterococcus faecalis isolates and also in E. faecalis in the control strains. The aggregation substance gene (as) was only amplified in LUB93101 isolate. Interestingly, esp gene was not detected in any of the isolates. Conclusion: Despite resistance to vancomycin and presence of some pathogenicity related genes in this study, E. faecalis isolates may not be human pathogens due to lack of pathogenic factors. The esp gene is crucial for biofilm formation and rise of nosocomial infections. Donkey’s milk Enterococcus faecalis isolates are not able to form biofilm and seem not to bring any problem.

Background and purpose: Lactic acid bacteria (LAB) play an important role in human and other organisms life. Some of LABs kill pathogenic and other harmful microorganisms. Enterococcus are, gram-positive, catalase-negative, cocci forming, non-sporogenesis, and facultative anaerobic bacteria. This study was done to identify and isolate possible probiotic bacteria with benefits to human health from Persian oak sap (Quercus brantii var. persica). The aim was to identify beneficial bacteria for plant pathogenic biological control and industrial applications. Materials and methods: LABs were identified using conventional methods, including culture dependent methods and 16S rRNA sequencing method. Antibiogram analysis was performed and the presence of virulence genes, including efaA (endocarditis antigen), as, ace, esp and gelE was examined by PCR. Results: It was found that out of 285 colonies, 160 (56.1%) were catalase-negative and gram-positive. Results of 16S rRNA sequencing showed that the bacteria isolated bacteria belong to the Enterococcus Faecium species. E. faecium strains of this study were sensitive to a number of clinically important antibiotics such as vancomycin, ampicillin, ciprofloxacin, and nitrofurantoin. Two strains of E. faecium bacteria, one with the ability to produce Co2 from glucose (KX185054) and one with no Co2 production ability (KX185055) were identified. The 16S rRNA sequence of identified strains were deposited in NCBI database. PCR amplification did not amplify virulence genes except efaA (endocarditis antigen). Conclusion: In this study, two different E. faecium strains were isolated from the oak which can be good candidates for probiotics and biological control.