Timilsina Sujan, Minsavage Gerald V, Preston James, Newberry Eric A, Paret Matthews L, Goss Erica M, Jones Jeffrey B, Vallad Gary E
Deparment of Plant Pathology, University of Florida, Gainesville, FL 32611, USA.
Gulf Coast Research and Education Center, University of Florida, Gainesville, FL 32611, USA.
Int J Syst Evol Microbiol. 2018 Jan;68(1):64-70. doi: 10.1099/ijsem.0.002445. Epub 2017 Nov 17.
An unusual fluorescent pseudomonad was isolated from tomato exhibiting leaf spot symptoms similar to bacterial speck. Strains were fluorescent, oxidase- and arginine-dihydrolase-negative, elicited a hypersensitive reaction on tobacco and produced a soft rot on potato slices. However, the strains produced an unusual yellow, mucoid growth on media containing 5 % sucrose that is not typical of levan. Based on multilocus sequence analysis using 16S rRNA, gap1, gltA, gyrB and rpoD, these strains formed a distinct phylogenetic group in the genus Pseudomonas and were most closely related to Pseudomonas viridiflava within the Pseudomonassyringae complex. Whole-genome comparisons, using average nucleotide identity based on blast, of representative strain GEV388 and publicly available genomes representing the genus Pseudomonas revealed phylogroup 7 P. viridiflava strain UASW0038 and P. viridiflava type strain ICMP 2848 as the closest relatives with 86.59 and 86.56 % nucleotide identity, respectively. In silico DNA-DNA hybridization using the genome-to-genome distance calculation method estimated 31.1 % DNA relatedness between GEV388 and P. viridiflava ATCC 13223, strongly suggesting the strains are representatives of different species. These results together with Biolog GEN III tests, fatty acid methyl ester profiles and phylogenetic analysis using 16S rRNA and multiple housekeeping gene sequences demonstrated that this group represents a novel species member of the genus Pseudomonas. The name Pseudomonas floridensis sp. nov. is proposed with GEV388 (=LMG 30013=ATCC TSD-90) as the type strain.
从表现出与细菌性斑点病症状相似的叶斑症状的番茄中分离出一株不寻常的荧光假单胞菌。该菌株具有荧光，氧化酶和精氨酸双水解酶阴性，在烟草上引发过敏反应，并在土豆片上产生软腐病。然而，这些菌株在含有5%蔗糖的培养基上产生了不寻常的黄色黏液状生长物，这并非典型的果聚糖。基于使用16S rRNA、gap1、gltA、gyrB和rpoD的多位点序列分析，这些菌株在假单胞菌属中形成了一个独特的系统发育群，并且与丁香假单胞菌复合体中的绿黄假单胞菌关系最为密切。使用基于blast的平均核苷酸同一性对代表性菌株GEV388和代表假单胞菌属的公开可用基因组进行全基因组比较，结果显示系统发育群7的绿黄假单胞菌菌株UASW0038和绿黄假单胞菌模式菌株ICMP 2848是最接近的亲缘菌株，核苷酸同一性分别为86.59%和86.56%。使用基因组到基因组距离计算方法进行的电子DNA-DNA杂交估计GEV388与绿黄假单胞菌ATCC 13223之间的DNA相关性为31.1%，强烈表明这些菌株是不同物种的代表。这些结果连同Biolog GEN III测试、脂肪酸甲酯谱以及使用16S rRNA和多个管家基因序列的系统发育分析表明，该类群代表假单胞菌属的一个新物种成员。提议将其命名为佛罗里达假单胞菌（Pseudomonas floridensis sp. nov.），以GEV388（=LMG 30013=ATCC TSD-90）作为模式菌株。
