Basic Characterization of Natural Transformation in Avibacterium paragallinarum

Area of Science:

• Microbiology
• Bacterial Genetics
• Molecular Biology

Background:

• Avibacterium paragallinarum causes infectious coryza (IC) in chickens, a disease with increasing prevalence.
• Limited gene manipulation methods hinder research into A. paragallinarum's genetics and pathogenesis.
• Natural transformation is a valuable gene transfer method in other Pasteurellaceae but unestablished in A. paragallinarum.

Purpose of the Study:

• To investigate the potential for natural transformation in A. paragallinarum.
• To identify genetic factors and competence proteins associated with natural transformation.
• To establish an efficient method for gene manipulation in A. paragallinarum.

Main Methods:

• Bioinformatic analysis to identify homologs of competence proteins from Haemophilus influenzae.
• Genome-wide search for uptake signal sequences (USS) in A. paragallinarum.
• Construction of plasmids with and without USS for transformation experiments.

Main Results:

• 16 homologs of H. influenzae competence proteins were identified in A. paragallinarum.
• The uptake signal sequence (ACCGCACTT) was highly abundant in the A. paragallinarum genome.
• Plasmids carrying the USS demonstrated significantly higher transformation efficiency in A. paragallinarum serovars A, B, and C.

Conclusions:

• Avibacterium paragallinarum possesses the capability for natural transformation.
• The established transformation method is stable, efficient, and applicable to multiple serovars.
• This breakthrough facilitates genetic manipulation, advancing research on A. paragallinarum and infectious coryza.