Biology subjects

Coradetti, S.

Publications and source records attributed to Coradetti, S..

4 recordsLinked to original sources

bioRxiv2026

Antimicrobial peptides expressed by plant-engineered 'symbiont' technology reduces titers and disease symptoms of "Candidatus Liberibacter solanacearum" in potato

Delivery of therapeutic biomolecules into plant vascular tissues remains a challenge in management of vector-borne plant pathogens. The symbiont concept uses reprogrammed Agrobacterium tumefaciens galls (called symbionts) to produce biomolecules while remaining connected to host vasculature. We evaluated whether symbionts expressing antimicrobial peptides (AMPs) suppress Candidatus Liberibacter solanacearum (CLso), the causal agent of potato zebra chip disease. Symbionts were engineered to express a Streptococcus mutans bacteriocin associated with bacterial membrane disruption (Blp-Sm), or an AMP isolated from finger lime and associated with resistance to citrus greening disease (MaSAMP). Effects of AMP-producing symbionts on CLso titers, infection incidence, pathogen movement, and disease symptoms were evaluated in tomato and potato. In tomato, neither AMP significantly reduced CLso titers or infection incidence. However, in potato, AMP-producing symbionts reduced CLso accumulation and movement from CLso-inoculated source shoots into non-inoculated sink shoots connected through underground tubers. Blp-Sm produced the strongest reduction in CLso accumulation and infection incidence in sink tissues. In separate assays where symbionts were established directly on potato seed tubers, MaSAMP significantly reduced CLso titers in stems and tubers and reduced zebra chip symptoms in tubers, despite no reduction of CLso titers in terminal leaves. These findings demonstrate that AMP-producing symbionts suppress vascular pathogen accumulation and movement within plants and highlight the symbiont concept as a potential platform for managing diseases caused by vascular-restricted pathogens. Further, they show the potato-CLso system is a promising infection model to both refine and improve symbiont technology, and to test additional AMPs for potency against related pathogens.

plant biology↗

bioRxiv2026

A scalable approach to inoculate plant viral vectors into plant tissue using non-pathogenic, transgenic galls

Vascular plant pathogens transmitted by insects inflict devastating economic losses on crops worldwide. By obstructing and usurping the natural flow of nutrients, plant infection by these pathogens drastically reduces yields, vigor and productivity. Treating fruit-bearing trees against persistent vascular pathogens poses a unique challenge, as systemic delivery of therapeutics must navigate the compartmentalized architecture of the trees vascular system under changing environmental conditions without disrupting fruit production or long-term tree health. Plant viruses have gained traction as a novel approach to deliver therapies to crop plants, including fruit trees, but delivery of viral vectors to orchards at scale remains a significant challenge. We tested whether transgenic galls can be used to systemically infect plants with a plant virus infectious clone. We combined the plant growth regulator gene cassette from Agrobacterium tumefaciens strain C58 with the wild-type strain of citrus yellow vein associated virus-1 (CY1) on a single plasmid within the T-DNA for plant cell transformation. Using EHA105, a disarmed strain of A. tumefaciens, we inoculated stems with these gall-forming plasmids and initiated systemic CY1 infection in citrus and Arabidopsis thaliana over three independent experiments. We provide proof-of-concept that transgenic galls, referred to as symbionts, can launch the systemic infection of CY1 in economically important and model plants. Symbiont delivery of therapeutic viral vectors is theoretically scalable from inoculation of mother trees within the nursery to millions of trees in the field and may be a valuable tool for the commercial delivery of therapeutic plant viral vectors.

plant biology↗

bioRxiv2025

The "Grove-First" Framework: Starting in the Grove to Find Therapies for Huanglongbing

Citrus greening disease, also known as huanglongbing (HLB), is the most serious vector-borne bacterial disease of citrus world-wide1,2. There is an immediate global need to provide the citrus industry with relief from HLB and a return to profitable citrus production. Standard screening methods for HLB therapeutic treatments typically involve various laboratory-based assays to select treatments with antimicrobial properties3, which then advance to greenhouse and eventually field testing in a workflow that takes multiple years. Unlike traditional lab-first screening, we present a design of experiments framework4,5, referred to as Grove-First, that rapidly screens treatments with regulatory-friendly profiles in commercial citrus groves using trunk injection to select treatments that improve tree health and fruit yield over the course of a single growing season. Using this framework, we identified candidate treatments with effects comparable to or better than the standard oxytetracycline (OTC) on visual tree-health and/or yield indices in an initial screen of HLB-positive 8-year-old Valencia sweet orange trees. Expanded trials in commercial citrus groves allowed us to validate the initial screening results at other locations and in other citrus varieties. Grove-First rapidly accelerated the identification and large-scale field testing of HLB therapies, some of which are available for growers to use immediately and others that require further field testing and/or regulatory actions.

plant biology↗

bioRxiv2017

Functional genomics of lipid metabolism in the oleaginous yeast Rhodosporidium toruloides

The basidomycete yeast Rhodosporidium toruloides (a.k.a. Rhodotorula toruloides) accumulates high concentrations of lipids and carotenoids from diverse carbon sources. It has great potential as a model for the cellular biology of lipid droplets and for sustainable chemical production. We developed a method for high-throughput genetics (RB-TDNAseq), using sequence-barcoded Agrobacterium tumefaciens T-DNA insertions into the R. toruloides genome. We identified 1337 putative essential genes with low T-DNA insertion rates. We functionally profiled genes required for fatty acid catabolism and lipid accumulation, validating results with 35 targeted deletion strains. We found that both mitochondrial and peroxisomal enzymes were required for growth on fatty acids, with different peroxisomal enzymes required on different fatty acids. We identified a high-confidence set of 150 genes affecting lipid accumulation, including genes with predicted function in signaling cascades, gene expression, protein modification and vesicular trafficking, autophagy, amino acid synthesis and tRNA modification, as well as genes of unknown function. These results greatly advance our understanding of lipid metabolism in this oleaginous species, identify key biological processes to be further explored and optimized for production of lipid-based bioproducts, and demonstrate a general approach for barcoded mutagenesis that should enable functional genomics in diverse fungi.

systems biology↗