Article Bacterial Proteins Citrus Fimbriae Proteins Gene Deletion Plant Diseases Virulence Xanthomonas Xanthomonas citri Xanthomonas citri subsp. citri bacterial colonization bacterial gene bacterial growth bacterial plant disease bacterial protein bacterial strain bacterial virulence bacterium adherence biofilm controlled study fimA gene fimA1 gene fimbria protein gene deletion gene identification gene mutation genetics metabolism microbiology nonhuman