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Objective Lactic acid bacteria (LAB) synthesize valuable industrial and pharmaceutical important biopolymers, such as Alternan, by expressing glycosyltransferase enzymes by utilizing extracellular sucrose. In this study, due to the importance of such versatile biopolymers in the industry and medicine, a gene encoding an Altranansucrase (Asr) was introduced to sugar beet plants. Materials and methods A gene encoding the Asr gene was isolated from Leuconostoc mesenteroides bacterium and introduced to sugar beet plants by using Agrobacterium-mediated transformation. Molecular techniques were used to analyse transgenic plants and sugar content of sugar beet lines. Results Out of 131 transformed explants, only three transgenic plants were produced, showing a transformation efficiency of 2.3%. The Asr gene integration in transgenic plants genome and expression were confirmed by specific PCR and semi-quantitative RT-PCR analysis, respectively. Sugar analysis of sugar beet transgenic plants showed that control plants with a 19.6% brix value (Sucrose) had more sucrose than transgenic plants with an average brix value of 14.4%. Brix in transgenic plants was lower than that of control plants. The amount of sugar (sucrose) in the transgenic asr-expressing plants reduced by 36.1% relative to the untransformed control plants. Conclusions The results of this study showed that Altrenansucrase can convert substantial amount of sugar beet sucrose into Alternan biopolymer, producing 36.6 mg/g FW alternan biopolymer with pharmaceutical and industrial applications.

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.

Introduction Despite the fact that Iran is one of the major chickpea (Cicer arietinum L.) center of origins, limited information is available regarding chickpea genetic variation and diversity. Genetic diversity information is crucial for the choice of proper parents to establish new breeding programs. Chickpea germplasm is poor, suggesting the need for gaining enough knowledge of genetic diversity among available chickpea genotypes. A number of molecular techniques have been developed to unveil the genetic potentials of plant materials. Random Amplified Polymorpic DNA (RAPD) seems to be a reliable molecular marker to investigate the genetic diversity of chickpea genotypes in IRAN. The objectives of present research was: (1) to investigate the power of RAPD markers for estimation of genetic diversity among chickpea genotypes in west of Iran, (2) to investigate the genetic relationships between chickpea genotypes, and (3) to determine whether chickpea genotypes could be distinguished by RAPD marker data. Materials and Methods Random amplified polymorphic DNA markers (RAPD) were used to assess the genetic relationship between 18 different chickpea genotypes representing the cultivated chickpea cultivars in west of Iran. Genomic DNA was isolated according to Murray & Thompson (1980). Eighteen oligonucleotide primers were selected according to the number of literature published with the highest number of polymorphic bands. Polymerase chain reaction (PCR) was carried out in a total volume of 25 μl including 2 units of Taq DNA polymerase, 30 ng of genomic DNA template, 10 pmol of primers, 0.2 mM of dNTPs, and 2.5 μl of 10 × reaction buffer. DNA amplifications were performed in a thermocycler. The thermal profile was as follow: One time denaturation at 94◦C (5 min), followed by 40 cycles of denaturation at 94◦C (3 min), annealing at each primer proper Tm (1 min) and extension at 72◦C (2 min) and one time final extension at 72◦C (5 min). PCR products were analyzed on 1.5 % agarose gels in TBE buffer running at 100 V for 2h. The gels were stained using ethidium bromide and visualized with UV light. The reproducibility of the DNA band patterns was evaluated duplicate gel electrophoresis analysis. Only clear and repeatedly amplified RAPD DNA bands were scored as (1) for present bands and (0) for absent ones. Results and Discussion Out of 18 random RAPD primers used in this study, 17 primers amplified genomic DNA across all the genotypes. In total, 201 polymorphic bands (96.63%) out of 208 reproducibly scoreable RAPD markers were generated (OPM-05 primer did not produce any band). On average, 12.2 bands per primer were observed in RAPD analysis. Cluster analysis using Dice coefficient of similarity and UPGMA (r=0.98) method based on polymorphic fragments, grouped all eighteen genotypes into 6 groups with 77% accuracy. Based on dendrogram obtained, Bivanij (Landrace genotype) showed the least similarity with the 6th cluster. Although there was no redundancy among the genotypes tested, the majority of genotypes were clustered together. ICARDA genotypes may have been improved from an Iranian landrace. Conclusions Genetic diversity among chickpea cultivars using RAPD markers have been studied by a number of researchers. Although in most cases a low level of polymorphism with RAPD markers have been reported, this study showed a considerable amount of polymorphism. Furthermore, our results showed that cultivated chickpea cultivars in west of Iran have many genes in common. We recommend further studies to be conducted by using more number of chickpea genotypes as well as more robust molecular markers. Results of this study can be used in germplasm management/conservation practices, developing core collections and as guidance to plant geneticist and breeders for planning future explorations, and crop improvement purposes. These findings may help to avoid genetic vulnerability and erosion, keeping chickpea genetic diversity and germplasm.