Abstract
INTRODUCTION: Stenotrophomonas represents a group of bacteria that exhibit significant value in industrial and agricultural applications, while also posing pathogenic risks to humans. 704A1(T) was isolated from a patient with tuberculous pleurisy. Its 16S rRNA sequence showed the highest homology (99.72%) with a Stenotrophomonas strain without defined species classification. It is necessary to clarify the species 704A1(T) belonging to and its potential pathogenicity to humans. METHODS: Systematical evaluations including phenotypic and biochemical characteristics, antibiotic susceptibility, genomic sequencing were conducted. The pathogenicity and immunological characteristics were tested by intranasally inoculated C57BL/6J mice. RESULTS: 704A1(T) is Gram negative rod-shaped bacterium with flagella at single extreme. Showing highly similar with S. maltophilia, 704A1(T) also displayed distinct characteristic peaks in fatty acid profiling and MALDI-TOF analysis. 704A1(T) was resistance to 21 antibiotics, including four anti-tuberculosis drugs: rifampicin, streptomycin, rifabutin, and cycloserine. The average nucleotide identity (ANI) values of 704A1(T) compared to defined Stenotrophomonas species ranged from 80.03% to 89.6%, below than both the commonly accepted 95%-96% ANI threshold for prokaryote species and the 95% threshold suggested for Stenotrophomonas. Though no mortality was observed, 704A1(T) could cause severe consolidation in murine lung tissue and has the ability of hematogenous dissemination. CONCLUSION: Results supported the classification of 704A1(T) (=GDMCC 1.4133(T)) as a novel species within the genus Stenotrophomonas, for which the name Stenotrophomonas tuberculopleuritidis sp. nov. is proposed. 704A1(T) is a multi-antibiotic resistance strain with potentially stronger pathogenicity than S. maltophilia and requires more clinical attention. The isolation of 704A1(T) underscored the importance of sustained surveillance and taxonomic clarity of Stenotrophomonas species emerging from clinical environments.