First data obtained by shotgun proteomics from Nicotiana occidentalis infected by 'Candidatus Phytoplasma mali'

The protein content of Nicotiana occidentalis infected by the non-cultivable phytopathogenic mollicute ‘Candidatus Phytoplasma mali’ strain AT was determined by shotgun proteomics. 102 out of 497 predicted phytoplasma proteins were identified as expressed in shoot tissue. In addition, 940 proteins of N. occidentalis were detected. Results demonstrate the successful application of LTQ Orbitrap XL ETD™ mass spectrometer in detecting phytoplasma-specific proteins in protein mixtures. A high portion of proteins with unknown function was identified beside prominent proteins involved in translation. Several of the proteins with unknown function contain a signal peptide suggesting a potential pathogen-host interaction.