What is the minimum length of gltA gene required for phylogenetic analyzes in Bartonella?

Bartonellosis is an emerging serious diseases of zoonotic relevance caused by an expanding number of recently discovered species of Bartonella. Many studies use partial gltA gene sequencing as the method of choice for species attribution, and a plethora of studies have utilized only this gene to describe Bartonella diversity. We observe a lack of correspondence between the phylogenies constructed using the complete gltA gene sequences and the small gene fragment usually used in phylogenetic analyzes. Everything indicates that important changes occurred by using larger fragments. Therefore, it is of great importance to define a minimum gltA fragment length to be used in future phylogenetic analyzes, besides the use of other genes.