عنوان

'Candidatus Liberibacter asiaticus' Encodes Two Novel Autotransporters that Target to Mitochondria

Number

LA79c2350x

.Language of Text, Soundtrack etc

انگلیسی

Title Proper

'Candidatus Liberibacter asiaticus' Encodes Two Novel Autotransporters that Target to Mitochondria

General Material Designation

[Article]

First Statement of Responsibility

Hao, Guixia; Boyle, Michael; Zhou, Lijuan; Duan, Yongping

Text of Note

As a phloem-limited, intracellular bacterial pathogen, 'Candidatus Liberibacter asiaticus' (Las) has a significantly reduced genome and causes huanglongbing (HLB), a devastating disease of citrus worldwide.  In this study, we characterized two novel autotransporter proteins of Las, and redesignated them as LasA_I and LasA_II in lieu of the previous names Hyv_I and Hyv_II. Proteins secreted by the type V secretion system (T5SS), known as autotransporters, are large extracellular virulence proteins localized to the bacterial poles. Bioinformatic analyses revealed that LasA_I and LasA_II share the structural features of an autotransporter family containing large repeats of a passenger domain and a unique C-terminal translocator domain. When fused to the GFP gene and expressed in E. coli, the LasA_I C-terminus and the full length LasA_II were localized to the bacterial poles, similar to other members of autotransporter family. Despite the absence of the signal peptide, LasA_I was found to localize at the cell surface by immuno-dot blot using a monoclonal antibody against the partial LasA_I protein. Its surface localization was also confirmed by the removal of the LasA_I antigen using a proteinase K treatment of the intact bacterial cells. When co-inoculated with a P19 gene silencing suppressor and transiently expressed in tobacco leaves, the GFP-LasA_I translocator targeted to the mitochondria. This is the first report that Las encodes novel autotransporters that target to mitochondria. These findings may lead to a better understanding of the pathogenesis of this intracellular "energy parasitic" bacterium, and to more efficient characterizing new molecular targets for HLB control.

Date of Publication

2014

Title

Journal of Citrus Pathology

Volume Number

1

Entry Element

Hao, Guixia; Boyle, Michael; Zhou, Lijuan; Duan, Yongping

Electronic name

[Article]

275578

a

Y