عنوان

Restriction-modification systems and genetic variability of Xanthomonas oryzae pv. oryzae

شماره

TLpq304051821

زبان متن نوشتاري يا گفتاري و مانند آن

انگلیسی

عنوان اصلي

Restriction-modification systems and genetic variability of Xanthomonas oryzae pv. oryzae

نام عام مواد

[Thesis]

نام نخستين پديدآور

S.-H. Choi

نام ساير پديدآوران

J. E. Leach

نام ناشر، پخش کننده و غيره

Kansas State University

تاریخ نشرو بخش و غیره

1993

نام خاص و کميت اثر

170

جزئيات پايان نامه و نوع درجه آن

Ph.D.

کسي که مدرک را اعطا کرده

Kansas State University

امتياز متن

1993

متن يادداشت

The XorII methyltransferase gene (xorIIM) and very short patch repair endonuclease gene (xorii-vsr) were cloned from Xanthomonas oryzae pv. oryzae, the rice bacterial leaf blight pathogen. The xorIIM encodes a polypeptide of 47 KD and was identified as a monospecific m5cytosine methyltransferase gene. The xorii-vsr encodes a polypeptide of 19.7 KD and the gene is similar in sequence and size to the E. coli vsr gene of the DNA cytosine methylase system (Dcm). A population of X. oryzae pv. oryzae strains from major rice growing countries in Asia was evaluated for the presence or absence of the XorI and XorII restriction-modification (R-M) systems. Four clonal populations with the phenotypes usdXor{\rm I}\sp+{\rm II}\sp+,\, Xor{\rm I}\sp+{\rm II}\sp-,\ Xor{\rm I}\sp-{\rm II}\sp+,usd and usdXor{\rm I}\sp-{\rm II}\sp-usd were distributed in Asia. The XorII R-M system was predominantly found in southeast Asia, whereas the XorI modification system was most prevalent in northeast Asia. DNA polymorphisms were observed between strains in genomic sequences containing the XorII R-M genes; however, most Philippine strains and all the Indonesian and Korean strains had identical patterns. Based on the geographic distribution of both systems and the genome organization around the XorII system, I propose that the XorI system originated in northeast Asia and moved to southeast Asia, while the XorII system originated in southeast Asia. The existence of several phenotypes in some parts of Asia indicate that after movement of the systems the populations remained clonal. A marker-exchange mutant in which the avirulence gene locus avrXa7 was insertionally inactivated was significantly reduced in aggressiveness to susceptible rice cultivars. Aggressiveness was restored by complementation with a plasmid bearing the avrXa7 gene. Thus, avrXa7 codes for not only resistance-gene-specific avirulence function, but also for pathogenicity functions.

موضوع مستند نشده

Biological sciences

موضوع مستند نشده

Microbiology

موضوع مستند نشده

Molecular biology

موضوع مستند نشده

Molecular biology

موضوع مستند نشده

Plant pathology

موضوع مستند نشده

Plant pathology

مستند نام اشخاص تاييد نشده

J. E. Leach

مستند نام اشخاص تاييد نشده

S.-H. Choi

نام الکترونيکي

فرمت انتشار

p

نوع ماده

[Thesis]

کد کاربرگه

276903

سطح دسترسي

a

تكميل شده

Y