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Selection of transgenic plants by using genes encoding screenable markers of plant origin with health benefit properties, such as anthocyanin is an important aim in plant genetic engineering. In this study, Malus domestica MYB10 (MdMYB10) gene, was used for Agrobacterium tumefaciens-mediated transformation of two SBS-02 and SBS-04 sugar beet lines. The impact of different light regimes on plant tissue culture from a combination of light, dark/light and dark was investigated. The results of this study showed that the MdMYB10 gene was successfully integrated into the selected purple transgenic lines, suggesting that the expression of MdMYB10 gene in sugar beet shoots can be used as a screenable markers for transformation, possibly replacing antibiotic resistant genes. Furthermore, the results of the antibacterial activity of transgenic plants extracts showed that the total extract obtained from transgenic lines significantly (P

Expression of strong antimicrobial peptides in plants is of great interest to combat a wide range of plant pathogens. To bring the Dermaseptin B1 (DrsB1) peptide to the intimate contact of the plant pathogens cell wall surface, the DrsB1 encoding sequence was fused to the C-terminal part of the two copies of the chitin-binding domain (CBD) of the Avr4 effector protein and used for Agrobacterium rhizogenes-mediated transformation. The expression of the recombinant protein in the tobacco hairy roots (HRs) was confirmed by molecular analysis. Antimicrobial activity analysis of the recombinant protein purified from the transgenic HRs showed that the (CBD)2-DrsB1 recombinant protein had a significant (p

Due to its high productivity and sucrose content, sugarcane (Saccharum officinarum) is becoming the source of high-value bioproducts. Expression of bacterial extracellular polysaccharide genes in non-biopolymer accumulating plants is an excellent resource for production of added-value products. To this end, an expression cassette containing a full-length glucosyltransferase (gtfI) gene from Streptococcus downei driven by a CaMV promoter was expressed in a commercial sugarcane cultivar (CP48-103) using a biolistic approach. Copy number was assessed for a number of selected transgenic sugarcane lines by DNA blot analysis, where it was corroborated that each transgenic line contained at least two gtfI copies. The southern blot analysis of gtfI-expressing lines showed that the number of integrated copies ranged from two to four. The expression of gtfI in transgenic sugarcane plants was confirmed by mRNA blot analysis and qRT-PCR analysis. The expression of gtfI in transgenic sugarcane plants resulted in an approximate 30% reduction in sucrose accumulation, suggesting that mutansucrase actively converted sucrose to mutan polymer. In internodal stalk tissues, mutan polymer accumulated up to 55.9 mg/g FW, which apparent through glucan staining. The levels of glucose and fructose increased nearly by twofold, suggesting that mutansucrase may also have hydrolyzing activity.

An antibacterial peptide-encoding gene from alfalfa seeds, alfAFP, was fused to the C-terminal part of chitin-binding domain (CBD) of the rice chitinase-encoding gene (CBD-alfAFP) and introduced to tobacco by Agrobacterium-mediated transformation. Polymerase chain reaction (PCR) technique was used to confirm the integration of the recombinant CBD-alfAFP encoding gene in transgenic tobacco plants. A number of transgenic lines and a non-transgenic control plant were selected for further molecular analyses. The result of analyzing the transgenic plants by semi-quantitative RT-PCR showed that the recombinant gene is expressed in transgenic plants and there is a difference between the transgenic plants in terms of the level of CBD-alfAFP expression. The total protein was extracted from a few selected transgenic plants and used to evaluate the antibacterial/antifungal of recombinant protein activity against some important plant and human pathogens. The results of this experiment showed that the total protein extract obtained from transgenic lines significantly (P

Background Contamination of food and agricultural crops by Fusarium species is a major concern of food spoilage and a potential public health hazard. In the present study, natural contamination of maize and wheat samples from main cultivation areas of Iran by Fusarium species belonging to the Giberella fujikuroi species complex was evaluated, with special attention to the ability of the isolates to produce fumonisin B1 (FB1 ). Results A total of 55 Fusarium isolates were obtained from 27/32 maize samples (84.4%) and 11/15 wheat samples (73.3%). They were identified as F. verticillioides (47.3%), F. proliferatum (47.3%), F. fujikuroi (1.8%), F. nygamai (1.8%) and F. redolens (1.8%) by sequence analysis of translation elongation factor 1-α (TEF1-α). Twenty-two of 55 Fusarium isolates belonging to F. proliferatum (23.6%), F. verticillioides (14.5%) and F. fujikuroi (1.8%) produced FB1 in the concentration range 230.4-9565.0 µg mL(-1) . The dendrogram resulting from the TEF1-α profile showed that the genotypes were divided into clusters I, II and III, of which cluster III contained only F. redolens, its first report from Iran. Conclusion On the basis of in vitro FB1 biosynthesis of the analyzed strains, the high degree of contamination of maize and wheat with Fusarium strains reported here should be considered as a potential public health threat, because a meaningful number of the isolates were found to produce hazardous levels of carcinogenic FB1 .

To identify miRNAs and assess the expression of genes involved in drought stress tolerance, leaf and root ESTs were analyzed in barley. To this end, the EGassembler bioinformatics service and IDEG6 were used for the pre-processing and identify differentially expressed genes among EST libraries, respectively. Furthermore, root contigs were analyzed by C-mii software for miRNAs identification. The expression profile of two drought tolerance candidate genes was studied, using Real time-PCR in a 2 (Nimruz and Spontaneum) × 2 (control and 50% FC) factorial experiment in a completely randomized design with 3 replications. Results of this study showed that N-butyl-N-methylpiperidinium (Pip1;4) and a non-specific lipid transport protein (nsLTP) were found to express differently under drought stress. The expression level of barley HvPip1;4 (HvPiP1;4) and non-specific lipid transport (HvnsLTP) genes increased by 95.98 and 54.53 fold after 72 h of drought stress, respectively. There was a significant difference (P

The original version of this article unfortunately contained a mistake in the unit “μg/l”. The unit “μg/l” should be corrected to “μg/ml” throughout the paper.

Starch is used in many industrial applications, but often requires chemical derivatization to enhance its properties before use. In particular, the stability of starch polymers in solution is improved by acetylation. A drawback of this treatment is the use of pollutant chemicals. A biological alternative to chemical derivatization was investigated by the expression of an amyloplast-targeted Escherichia coli maltose acetyltransferase (MAT) gene in tubers of wild-type (Kardal) and mutant amylose-free (amf) potato plants. MAT was expressed as such, or fused to the N- or C-terminus of a non-catalytic starch-binding domain (SBD) to target the starch granule. Starch granules derived from transgenic plants were found to contain acetyl groups, although their content was low, opening up an avenue to move away from the post-harvest chemical derivatization of starch. MAT inside starch granules was found to be active post-harvest when supplied with acetyl-coenzyme A and glucose or maltose, but it did not acetylate starch polymers in vitro. Starch granules from transformants in which MAT alone was expressed also showed MAT activity, indicating that MAT is accumulated in starch granules, and has affinity for starch by itself. Furthermore, starch granule morphology was altered, and fusion proteins containing MAT and SBD seemed to have a higher affinity for starch granules than two appended SBDs. These results are discussed against the background of the quaternary structure of MAT.

It has been shown previously that mutan can be co-synthesized with starch when a truncated mutansucrase (GtfICAT) is directed to potato tuber amyloplasts. The mutan seemed to adhere to the isolated starch granules, but it was not incorporated in the starch granules. In this study, GtfICAT was fused to the N- or C-terminus of a starch-binding domain (SBD). These constructs were introduced into two genetically different potato backgrounds (cv. Kardal and amf), in order to bring GtfICAT in more intimate contact with growing starch granules, and to facilitate the incorporation of mutan polymers in starch. Fusion proteins of the appropriate size were evidenced in starch granules, particularly in the amf background. The starches from the various GtfICAT/SBD transformants seemed to contain less mutan than those from transformants with GtfICAT alone, suggesting that the appended SBD might inhibit the activity of GtfICAT in the engineered fusion proteins. Scanning electron microscopy showed that expression of SBD-GtfICAT resulted in alterations of granule morphology in both genetic backgrounds. Surprisingly, the amf starches containing SBD-GtfICAT had a spongeous appearance, i.e., the granule surface contained many small holes and grooves, suggesting that this fusion protein can interfere with the lateral interactions of amylopectin sidechains. No differences in physico-chemical properties of the transgenic starches were observed. Our results show that expression of granule-bound and "soluble" GtfICAT can affect starch biosynthesis differently.

The Escherichia coli glycogen branching enzyme (GLGB) was fused to either the C- or N-terminus of a starch-binding domain (SBD) and expressed in two potato genetic backgrounds: the amylose-free mutant (amf) and an amylose-containing line (Kardal). Regardless of background or construct used, a large amount of GLGB/SBD fusion protein was accumulated inside the starch granules, however, without an increase in branching. The presence of GLGB/SBD fusion proteins resulted in altered morphology of the starch granules in both genetic backgrounds. In the amf genetic background, the starch granules showed both amalgamated granules and porous starch granules, whereas in Kardal background, the starch granules showed an irregular rough surface. The altered starch granules in both amf and Kardal backgrounds were visible from the initial stage of potato tuber development. High-throughput transcriptomic analysis showed that expression of GLGB/SBD fusion protein in potato tubers did not affect the expression level of most genes directly involved in the starch biosynthesis except for the up-regulation of a beta-amylase gene in Kardal background. The beta-amylase protein could be responsible for the degradation of the extra branches potentially introduced by GLGB.