Xanthomonas citri
| Xanthomonas citri | |
|---|---|
| |
| Bacterial X. citri black spot on a mango, note that each black lesion has “cracks” | |
Scientific classification 
| |
| Domain: | Bacteria |
| Kingdom: | Pseudomonadati |
| Phylum: | Pseudomonadota |
| Class: | Gammaproteobacteria |
| Order: | Xanthomonadales |
| Family: | Xanthomonadaceae |
| Genus: | Xanthomonas |
| Species: | X. citri
|
| Binomial name | |
| Xanthomonas citri (Hasse 1915) Gabriel et al. 1989
| |
Xanthomonas citri is a Gram-negative, rod-shaped bacterium. Although it is harmless for humans, it is a phytopathogen, known for being the causing agent of citrus canker.
Many pathovars are misclassified as X. cissicola, X. campestris, or X. axonopodis. A 2022 study proposes moving 20 pathovars in these three (including the sole representative of X. cissicola) into X. citri.[1] However, based on the principle of priority, all "X. citri" should become instead named under the earliest-published name, X. cissicola like in GTDB.[2] The two proposals do not affect the independence of X. campestris and X. axonopodis, as their type strains are sufficiently distinct from X. citri/cissicola to be their own species.
Pathovars included
[edit]Uncited entries are based on Bansal et al. (2022),[1] either in the article's own results (20 pathovars) or in its description of earlier results. Pathovars that include the type strain of either X. citri or X. cissicola are shown in bold.
- citri
- viticola
- vitiswoodrowii
- bauhiniae
- martyniicola
- vitiscarnosae
- vitistrifoliae
- khayae
- cissicola
- melhusii
- bilvae
- azadirachtae
- durantae
- cajani
- clitoriae
- centellae
- thespesiae
- leeana
- sesbaniae
- merremiae
- thirumalacharii
- trichodesmae
- aurantfolii[3]
The list is unlikely to be complete.
Bacterial killing via a secretion system
[edit]Xanthomonas citri uses its type IV secretion system to kill other Gram-negative bacterial species in a contact-dependent manner. The secretion of the effector proteins requires a conserved C-terminal domain, and its bacteriolytic activity is neutralized by a cognate immunity protein.[4][5]
Defense against predators
[edit]Xanthomonas citri also uses type VI secretion system in defense against the predatory amoeba Dictyostelium discoideum.[6]
References
[edit]- ^ a b Bansal, Kanika; Kumar, Sanjeet; Patil, Prabhu B. (June 2022). "Phylo-Taxonogenomics Supports Revision of Taxonomic Status of 20 Xanthomonas Pathovars to Xanthomonas citri". Phytopathology. 112 (6): 1201–1207. Bibcode:2022PhPat.112.1201B. doi:10.1094/PHYTO-08-21-0342-SC. PMID 34844415.
- ^ Chuvochina, M (9 November 2022). "s_Xanthomonas cissicola reclassificaiton". GTDB Forum.
- ^ "GCA_004329295.1 Xanthomonas cissicola". GTDB. – all GTDB search results for "aurantfolii" are classified as X. cissicola.
- ^ Souza DP, Oka GU, Alvarez-Martinez CE, Bisson-Filho AW, Dunger G, Hobeika L, Cavalcante NS, Alegria MC, Barbosa LR, Salinas RK, Guzzo CR, Farah CS (2015). "Bacterial killing via a type IV secretion system". Nature Communications. 6: 6453. Bibcode:2015NatCo...6.6453S. doi:10.1038/ncomms7453. PMID 25743609.
- ^ Sgro GG, Costa TR, Cenens W, Souza DP, Cassago A, Coutinho de Oliveira L, Salinas RK, Portugal RV, Farah CS, Waksman G (2018). "Cryo-EM structure of the bacteria-killing type IV secretion system core complex from Xanthomonas citri". Nature Microbiology. 3 (12): 1429–1440. doi:10.1038/s41564-018-0262-z. PMC 6264810. PMID 30349081.
- ^ Bayer-Santos, Ethel; Lima, Lídia dos Passos; Ceseti, Lucas de Moraes; Ratagami, Camila Yuri; de Santana, Eliane Silva; da Silva, Aline Maria; Farah, Chuck Shaker; Alvarez-Martinez, Cristina Elisa (2018). "Xanthomonas citri T6SS mediates resistance to Dictyostelium predation and is regulated by an ECF σ factor and cognate Ser/Thr kinase". Environmental Microbiology. 20 (4): 1562–1575. Bibcode:2018EnvMi..20.1562B. doi:10.1111/1462-2920.14085. ISSN 1462-2912. PMID 29488354. S2CID 3579518.
  | This Gammaproteobacteria-related article is a stub. You can help Wikipedia by expanding it. |