Bacterial expression of an effector protein of yellow rust pathogen and a resistance protein of wheat and characterization of the effector protein

Erdoğan, Sayıt Mahmut
Yellow rust is one of the most important wheat disease encountered in large parts of the world and in our country caused by a pathogen which is called as Puccinia striiformis f. sp. tritici (Pst). Rapid alterations in the pathogen virulency can make previously resistant varieties susceptible to the disease. Finding out common or species-specific genes, participated in the plant-pathogen interactions will provide an understanding of the biological mechanisms of the disease. Within the scope of this thesis followings were carried out: Coding region of TaYr10 protein, which resists Avr containing pathogen races, were separated into its domains and these domains were expressed in E.coli expression strains and purified by Immobilized Metal Affinity Chromatography (IMAC), Ultrafiltration and Size Exclusion Chromatography (SEC). Similarly, coding gene of the candidate effector protein of Puccinia striiformis f. sp. tritici (Pst), pstSCR1 which causes disease was expressed in E.coli expression strains and purified by IMAC, ultrafiltration and SEC. Among the studied proteins, only PstSCR1 protein achieved the requisite amount and purity to further study the structural analysis. Using the pure PstSCR1 protein, structural analyses were carried vi out by SAXS and NMR and as a result, 3D structure of the protein was identified in nanometer levels by SAXS. Additionally, secondary structure of the PstSCR1 protein was identified by CDS and the melting point of the protein was determined DSF. The data obtained in these studies provide important clues at the molecular level for the future studies about the disease mechanism of the pathogen and possible effector-resistance protein interactions.


Genetic screening of Turkish wheat varieties for the durable resistance gene, Lr34
Boylu, Barış; Akkaya, Mahinur S.; Hakkı, Erdoğan Eşref; Department of Biotechnology (2011)
Wheat diseases such as rusts and powdery mildews are among the most important and ancient diseases that affect wheat cultivation worldwide. The pathogen race specific resistance genes cannot maintain long lasting resistance. On the other hand, the presence of genes confers the non-race specific resistance last much longer. The durable resistance phenotypes in wheat against various rust and powdery mildew diseases were reported as Lr34, Yr18, and Pm38 separately; nevertheless, they were known to locate very ...
Characterization of a candidate effector of wheat yellow rust targeting chloroplast with a novel transit peptide
Andaç, Ayşe; Akkaya, Mahinur S.; Gür Dedeoğlu, Bala; Department of Biotechnology (2019)
Fungal pathogen, Puccinia striiformis f. sp. trtici, is the causative agent of stripe disease of wheat which causes disruption on wheat yield in many parts of the world. Fungal pathogens secrete effector molecules into host plant cells to suppress host immunity via virulence to colonize plants. Ongoing efforts are being made to identify and characterize effector proteins in many fungal plant pathogens. Nevertheless, the precise biological and biochemical functions of many effectors, such as their traffickin...
In Turkish wheat cultivars the resistance allele of LR34 is ineffective against leaf rust
Yildirim, Kubilay; Boylu, Baris; Atici, Elif; Kahraman, Turhan; Akkaya, Mahinur (2012-10-01)
Rust and powdery mildew diseases of wheat are among the oldest and most harmful diseases confining the yield of wheat worldwide. Development of resistant wheat cultivars with durable or race-nonspecific resistance genes is the main objective for many breeding programs. One of these genes, Lr34/Yr18/Pm38, was found to confer partial and durable resistance against rust pathogens as well as powdery mildew. This multiple disease resistant locus was recently found to comprise a single gene, which encodes an aden...
Cloning, transformation and wheat infiltration assay of a puccinia striiformis f. sp. tritici effector candidate
Özketen, Ahmet Çağlar; Akkaya, Mahinur S.; Department of Biotechnology (2013)
The stripe rust pathogen, Puccinia striiformis f. sp. tritici is the causative agent of the yellow (stripe) rust which is globally one of the most devastating and economically significant diseases in wheat. Although using fungicide can present a practical solution against the disease, an efficient, better and environmentally safer approach is needed to grow disease free wheat. To achieve this, better comprehension of the plant-pathogen interaction at the molecular and cellular level is required. The pathoge...
Site directed mutations of one of the plant pathogen effector gene for functional analysis
Mustafa, Zemran; Akkaya, Mahinur S.; Department of Biochemistry (2015)
Wheat (Triticum aestivum L.) is one of the most important crops planted in the world and used as major food resource. Yet, there are major losses of productivity due to different biotic and abiotic destructive agents. Among the biotic factors especially the yellow rust is one of the most frequent. Yellow rust or also called “stripe rust”, due to stripe like appearances on the leaves, disease is caused by Puccinia striiformis f. sp. tritici, which is an obligate plant fungal pathogen. To cope with high yield...
Citation Formats
S. M. Erdoğan, “Bacterial expression of an effector protein of yellow rust pathogen and a resistance protein of wheat and characterization of the effector protein,” Ph.D. - Doctoral Program, Middle East Technical University, 2019.