David Requena^{1, 2}, Ana Chumbe1, Michael Torres^{1, 2}, Ofelia Alzamora1, Manuel Ramirez^{1, 2}, Hugo Valdivia-Olarte^{1, 2}, Andres Hazaet Gutierrez^{1, 2, 3}, Ray Izquierdo-Lara¹, Luis Enrique Saravia¹, Milagros Zavaleta¹, Luis Tataje-Lavanda¹, Ivan Best¹, Manolo Fernández-Sánchez¹, Eliana Icochea^{1, 4}, Mirko Zimic^{1, 2} & Manolo Fernández-Díaz¹* – FARVET Research Group. ¹FARVET S.A.C. ²Laboratorio de Bioinformática y Biología Molecular, Laboratorios de Investigación y Desarrollo, Facultad de Ciencias y Filosofía. Universidad Peruana Cayetano Heredia. ³Institute for Immunology and Informatics, University of Rhode Island. ⁴Laboratorio de Patología Aviar. Facultad de Medicina Veterinaria, Universidad Nacional Mayor de San Marcos. Manolo Fernández-Díaz *Corresponding author. † Correspondencia al autor Dr. Manolo Fernandéz Díaz.

ABSTRACT

Background: Avibacterium paragallinarum, the causative agent of infectious coryza, is a highly contagious respiratory acute disease of poultry, which affects commercial chickens, laying hens and broilers worldwide.

METHODOLOGY

In this study, we performed the whole genome sequencing, assembly and annotation of a Peruvian isolate of A. paragallinarum. Genome was sequenced in a 454 GS FLX Titanium system. De novo assembly was performed and annotation was completed with GS De Novo Assembler 2.6 using the H. influenzae str. F3031 gene model. Manual curation of the genome was performed with Artemis. Putative function of genes was predicted with Blast2GO. Virulence factors were identified by comparison with the Virulence Factor Database.

RESULTS

The genome obtained has a length of 2.47 Mb with 40.66% of GC content. Seventy five large contigs (>500 nt) were obtained, which comprised 1,204 predicted genes. All the contigs are available in Genbank [GenBank: PRJNA64665]. A total of 103 virulence factors, reported in the Virulence Factor Database, were found in A. paragallinarum. Forty four of them are present in 7 species of Haemophilus, which are related with pathogenesis, virulence and host immune system evasion. A tetracycline-resistance associated transposon (Tn10), was found in A. paragallinarum, possibly acting as a defense mechanism.

DISCUSSION AND CONCLUSION

The availability of A. paragallinarum genome represents an important source of information for the development of diagnostic tests, genotyping, and novel antigens for potential vaccines against infectious coryza. Identification of virulence factors contributes to better understanding the pathogenesis, and planning efforts for prevention and control  of the disease.

 

To Access the original article, check the following link: http://www.ncbi.nlm.nih.gov/pubmed/23861570.