Telluria xinjiangensis sp. nov., a Gram-negative bacterium isolated from ripe melon fruit and its genetic characteristics

Abstract Background The genus Telluria (family Oxalobacteraceae, phylum Pseudomonadota ) comprises phylogenetically and ecologically diverse bacteria recovered from environmental, clinical, and plant-associated habitats. However, representatives associated with fresh fruit remain poorly characterized, and the diversity and functional potential of Telluria in ripe melon fruit are largely unexplored. Results A Gram-negative, strictly aerobic, rod-shaped bacterium, designated strain BAP21 T , was isolated from the surface of ripe melon ( Cucumis melo ) collected in Kashgar, Xinjiang Uyghur Autonomous Region, China. Polyphasic characterization based on the 16S rRNA gene showed the highest sequence similarity to Telluria suwonensis 5414 S-25 T (99.01%), followed by Massilia. litorea LPB0304 T (98.90%), Telluria niabensis 5420 S-26 T (98.71%), and T. haematophila CCUG 38,318 T (98.46%). Genome-based comparisons showed that BAP21 T had its highest ANI value of 87.89% with T. haematophila CCUG 38,318 T . Digital DNA–DNA hybridization (dDDH) values between our strain BAP21 T and the compared type strains of Telluria ranged from 22.4 to 29.4%, all substantially below the accepted species boundary. Cells grow at 4–45 °C and pH 5.0–10.0 (optimum 6.5–8.5). The strain BAP21 T hydrolyses CM-cellulose, DNA, casein, starch, aesculin, gelatin, and tyrosine. The cellular fatty acid profile was dominated by C 16:0 (27.0%), with C 12:0 detected at a low proportion (0.15%). Genome analysis revealed biosynthetic gene clusters encoding carotenoids, the antifungal polyketide ambruticin, ulleungmycin, and aryl polyenes, consistent with in vitro antifungal activity against Alternaria sp. Conclusions The combined phylogenetic, genomic, phenotypic, and chemotaxonomic evidence supports the recognition of strain BAP21 T as representing a novel species within the genus Telluria , for which the name Telluria xinjiangensis sp. nov. is proposed. The type strain is BAP21 T (= CCTCC AB 2026005 T = CGMCC 1.66504 T ). The isolation of T. xinjiangensis BAP21 T from ripe melon expands the known ecological diversity of Telluria and highlights the biosynthetic and functional potential of fruit-associated members of the genus.