A Thai-led team isolated three endophytic actinomycetes from roots of Glycosmis pentaphylla, Aegle marmelos and lime. Morphology, chemotaxonomy, 16S rRNA and genome comparisons distinguished them from close relatives, supporting the names Nocardia glycosmidis, Nocardia aegles and Nocardia citri, with type strains deposited in culture collections.
Key findings
- R6R-6T and R7R-8T had highest 16S similarities of 98.9% and 99.1% to N. xestospongiae, while R16R-3T had 98.5% to N. anaemiae. All three fell below accepted dDDH and ANI species thresholds. Type strains were deposited as TBRC 14548T/NBRC 115197T, TBRC 14549T/NBRC 115198T and TBRC 14550T/NBRC 115199T.
Why this matters globally
Validly characterised and deposited type strains let researchers worldwide work with the same organisms, improve database accuracy and enable reproducible study of metabolites, enzymes and endophytic functions.
Thai researcher contribution
The work links Burapha University, Chulalongkorn University, Kasetsart University and the BIOTEC-NSTDA Thailand Bioresource Research Center across isolation, genomics, taxonomy and strain deposition, with a collaborator from Guangxi Medical University.
Limitations to consider
This establishes taxonomic novelty, not therapeutic activity, safety or plant benefit. Because some Nocardia species are pathogenic, the new strains should not be assumed safe or probiotic without dedicated testing.