Understanding enemy’s weapons to an effective prevention: common virulence effects across microbial phytopathogens kingdoms

Abstract

Plant–pathogens interaction is an ongoing confrontation leading to the emergence of new diseases. The majority of the invading microorganisms inject effector proteins into the host cell, to bypass the sophisticated defense system of the host. However, the effectors could also have other specialized functions, which can disrupt various biological pathways of the host cell. Pathogens can enrich their effectors arsenal to increase infection success or expand their host range. This usually is accomplished by the horizontal gene transfer. Nowadays, the development of specialized software that can predict proteins structure, has changed the experimental designing in effectors’ function research. Different effectors of distinct plant pathogens tend to fold alike and have the same function and focussed structural studies on microbial effectors can help to uncover their catalytic/functional activities, while the structural similarity can enable cataloguing the great number of pathogens’ effectors. In this review, we collectively present phytopathogens' effectors with known enzymatic functions and proteins structure, originated from all the kingdoms of microbial plant pathogens. Presentation of their common domains and motifs is also included. We believe that the in-depth understanding of the enemy’s weapons will help the development of new strategies to prevent newly emerging or re-emerging plant pathogens.

Keywords:

• Plant pathogens
• virulence effectors
• common protein functions
• conserved protein domains
• effectors’ structure

Acknowledgements

The authors thank undergraduate student Sotiris Marinos for his art skills and insight during creation of Figure 1. K.K. and P.F.S. were supported by the General Secretariat of Research and Innovation (GSRI) through the project “Innovative plant protection technologies for quarantine pathogens of the Xanthomonadaceae family utilizing tools of Optoacoustic and Molecular Biology -INNOVA- PROTECT”, project code Τ1ΕΔΚ-01878. D.T. was supported by “The Vineyard Roads” (project code 2018ΣΕ01300000; part of the “Emblematic Research Action of National Scope for the exploitation of new technologies in the Agri-food sector, specializing in genomic technologies and pilot application in the value chains of olive, grapevine, honey and livestock”) financed by Greek national funds through the Public Investments Program (PIP) of the General Secretariat for Research & Technology (GSRT) 2019–2021.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

K.K. was supported by the General Secretariat of Research and Innovation (GSRI) through the project “Innovative plant protection technologies for quarantine pathogens of Xanthomonadaceae family utilizing tools of Optoacoustic and Molecular Biology - INNOVA-PROTECT”, Project code: Τ1ΕΔΚ-01878. D.T. was supported by the "The Vineyard Roads" (project code: 2018ΣΕ01300000) part of the "Emblematic Research Action of National Scope for the exploitation of new technologies in the Agri-food sector, specializing in genomic technologies and pilot application in the value chains of "olive", "grapevine", "honey "and "livestock”) » financed by Greek national funds through the Public Investments Program (PIP) of General Secretariat for Research & Technology (GSRT) Duration 2019-2021.