Spiroplasma kunkelii is a species of Mollicutes, which are small bacteria that all share a common cell wall-less feature.

These methods provided a general phylogeny, but large gaps in knowledge were made apparent when considering the possibility of horizontal gene transfer.

Studies mostly focus on the analysis of the 16S rRNA gene to define relations and build phylogenic trees.

However, to confirm the connections made from 16S rRNA analysis studies have started to analyze the house keeping genes within S.

Although they are transferred by insects, Spiroplasma kunkelii need plants in order to survive and grow.

Spiroplasma kunkelii uses the host insect vector for multiplication, but it uses plants for survival.

Spiroplasma are chemoorganoheterotrophs due to their consumption of organic carbon and their parasitic lifestyle.

Studies have found that S. kunkelii lack cytidine, dCMP deaminases, transaldolase and deoxyribose 5-phosphate aldolase enzymes.

Though cases of S. kunkelii are take very seriously, due to it being a vector borne pathogen, it is able to be transferred between plants while only requiring one infected insect.