Controlled replication of 'Candidatus Liberibacter asiaticus' DNA in citrus leaf discs. Issue 3 (20th January 2020)

• Record Type: Journal Article
• Authors: Attaran, Elham; Berim, Anna; Killiny, Nabil; Beyenal, Haluk; Gang, David R.; Omsland, Anders
• Is Part Of: Microbial biotechnology. Volume 13:Issue 3(2020:May)
• Page Start: 747
• Page End: 759
• Publication Date: 2020-01-20
• Subjects: Microbial biotechnology -- Periodicals; Biotechnology; Microbiology; 660.62
• DOI: 10.1111/1751-7915.13531
• Languages: English
• ISSNs: 1751-7915

Abstract

Summary: ' Candidatus Liberibacter asiaticus ' is a fastidious bacterium and a putative agent of citrus greening disease (a.k.a., huanglongbing, HLB), a significant agricultural disease that affects citrus fruit quality and tree health. In citrus, ' Ca. L. asiaticus ' is phloem limited. Lack of culture tools to study ' Ca. L. asiaticus ' complicates analysis of this important organism. To improve understanding of ' Ca. L. asiaticus '–host interactions including parameters that affect ' Ca. L. asiaticus ' replication, methods suitable for screening pathogen responses to physicochemical and nutritional variables are needed. We describe a leaf disc‐based culture assay that allows highly selective measurement of changes in ' Ca. L. asiaticus ' DNA within plant tissue incubated under specific physicochemical and nutritional conditions. qPCR analysis targeting the hypothetical gene CD16‐00155 (strain A4) allowed selective quantification of ' Ca. L. asiaticus ' DNA content within infected tissue. ' Ca. L. asiaticus ' DNA replication was observed in response to glucose exclusively under microaerobic conditions, and the antibiotic amikacin further enhanced ' Ca. L. asiaticus ' DNA replication. Metabolite profiling revealed a moderate impact of ' Ca. L. asiaticus ' on the ability of leaf tissue to metabolize and respond to glucose. Abstract : Incubation of ' Ca. L. asiaticus '‐infected citrus leaf discs under microaerobic conditions in the presence of glucose stimulates replication of pathogen DNA. The ability to control ' Ca. L. asiaticus ' DNA replication within infected leaf tissue will facilitate study of the interaction between ' Ca. L. asiaticus ' and citrus.