Citrus greening is caused by the bacterium Liberibacter asiaticus.
Citrus greening is caused by the bacterium Liberibacter asiaticus.

University of Florida researchers have sequenced the genome of Liberibacter crescens BT-1, a close cousin of the Liberibacter bacterium that causes citrus greening.

A group led by Mike Davis, a researcher at the Citrus Research and Education Center in Lake Alfred sequenced the genome, according to a news release.

They published their findings in the journal Standards of Genomic Standards.

One of the challenges researchers have faced with citrus greening is they haven't been able to culture Candidatus Liberibacter asiaticus in the laboratory.

Similar challenges also surround zebra chip, which is caused by a Liberibacter organism—Candidatus Liberibacter solanacearum.

Being able to reproduce them would significantly help with research.

So they turned to L. crescens, which can be cultured in the laboratory.

The researchers compared the genomes of BT-1 to the other two organisms to try to figure out why this strain could be cultured and the others can't.

They found that the three organisms shared about 75 percent similarities.

"The significance of this is that we now have available a cultured strain that we can use for antibiotic testing,"Jack Payne, senior vice president of agriculture and natural resources, Institute of Food and Agricultural Sciences, said in an email. "This should greatly speed the hunt for effective treatments."

The researchers also wanted to find clues into the virulence of L. asiaticus and L. solanacearum.

Although it appears that the two virulent organisms lack the ability to produce several essential amino acids, they said further researcher is needed to verify it.

Also involved in the sequencing were Michael Leonard, Jennie Fagen, Austin Davis-Richardson and Eric Triplett.