Sphingomonas melonis sp. nov., a novel pathogen that causes brown spots on yellow Spanish melon fruits

Abstract

A polyphasic taxonomic study was performed on the phytopathogenic bacterial strains DAPP-PG 224(T) and DAPP-PG 228, which cause brown spot on yellow Spanish melon (Cucumis melo var. inodorus) fruits. Based on the presence of glucuronosyl ceramide (SGL-1) in cellular lipids, the results of fatty acid analysis and 16S rDNA sequence comparison, the strains had been identified as belonging to the genus Sphingomonas and as phylogenetically related to Sphingomonas mali, Sphingomonas pruni and Sphingomonas asaccharolytica. The levels of 16S rDNA sequence similarity of these three species to strain DAPP-PG 224(T) were respectively 98.0, 98.0 and 97.4%. DNA-DNA hybridization experiments between strains pathogenic on melon fruit and S. mali, S. pruni and S. asaccharolytica revealed < or = 16% relatedness. Based on these results, the two isolates studied are regarded as independent from the type strains of the three species mentioned above. Sphingomonas strains from melon fruits are recognized as forming a genetically and phenotypically discrete species and to be differentiated by phenotypic characteristics from all 29 named species of the genus. Thus, the name Sphingomonas melonis sp. nov. is proposed for the isolates from diseased melon fruits. The type strain is DAPP-PG 224(T) (= LMG 19484(T) = DSM 14444(T)). The G+C content of DNA of the type strain is 65.0 mol%.

Culturable bacterial communities on leaf sheaths and panicles of rice plants in Japan

“…Sphingomonas isolates were verified to consist of three groups, and they were related to several reference species, such as S. parapaucimobilis, S. sanguis, S. paucimobilis, S. roseiflava, S. melonis, and S. aquatilis, based on the sequence similarities. Most of the reference Sphingomonas species in the dominant three clusters (S-a to S-c) have been obtained from plant (Takeuchi et al 1995;Yun et al 2000) or aquatic samples (Yabuuchi et al 1990;Denner et al 2001;Lee et al 2001;Asker et al 2007;Huo et al 2011;Zhang et al 2011), although S. melonis and S. suberifaciens have been known to cause brown spots on yellow Spanish melon fruits (Buonaurio et al 2002) and corky root of lettuce (van Bruggen et al 1990), respectively. This implies that the leaf sheaths of rice plants at heading time share some similarities with aquatic environments on the colonization for Sphingomonas species.…”

Biofilm-forming bacteria with varying tolerance to peracetic acid from a paper machine

“…Seventy-Wve percent of the bioWlm Table 2 16S rRNA gene sequence comparison data of bioWlm-forming bacterial isolates from bioWlms of a paper machine treated with peracetic acid Groups are as shown in Fig. 1 Table 3 Phenotypic characteristics of selected isolates (in bold) from bioWlms of a paper machine treated with peracetic acid Data for Sphingomonas-type strains with highest 16S rRNA gene sequence similarity to the paper machine isolates are quoted from published sources as follows: S. azotiWgens [50], S. pituitosa [10], S. trueperi [19], S. aquatilis [26], S. melonis [5], S. panni [8], and S. desiccabilis [38]. All isolates and type strains were negative for the production of indole, arginine dihydrolase, and urease isolates were members of the subclades S. trueperi (n = 39) and S. aquatilis (n = 6).…”

“…In contrast to the subclade S. trueperi, bioWlm formation by the subclade S. aquatilis was not reported hitherto. Species of this subclade were isolated from water (S. aquatilis [26]), brown spots on melons (S. melonis [5]), roots of trees and soil (S. desiccabilis [38]). So far there is no report on exopolysaccharides produced by this subclade.…”

Nicotine degradation by two novel bacterial isolates of Acinetobacter sp. TW and Sphingomonas sp. TY and their responses in the presence of neonicotinoid insecticides

“…Organic growth factors required --use ammonium or nitrate salts as a nitrogen source (Holt et al 1994). TY was oxidase-negative, grew in the presence of 3% NaCl and did not alkalinize Simmons' citrate medium, characteristics that were identical to the genus Sphingomonas melonis (Dong and Cai 2001;Buonaurio et al 2002). According to the Biolog GN identification, 40 of 95 carbon sources were easily utilized by strain TW, 14 were weakly utilized, and 41 were not utilized.…”