Insights into gut microbiota communities of Poecilobdella manillensis, a prevalent Asian medicinal leech
Microbiome study published in Journal of Applied Microbiology (2022)
Abstract
AIMS: Medicinal leeches (Annelida: Hirudinea) are fresh water ectoparasitic species which have been applied as traditional therapy. However, gut microbiota could bring high risks of opportunistic infections after leeching and arouses great interests. Here, gut bacterial and fungal communities of an Asian prevalent leech Poecilobdella manillensis were characterized and analysed through culture-independent sequencing. METHODS AND RESULTS: With high coverage in 18 samples (>0.999), a more complicated community was apparent after comparing with previous leech studies. A total of 779/939 OTUs of bacteria and fungi were detected from leech guts. The bacterial community was dominated by the phylum Bacteroidetes and Synergistetes. Genera Mucinivorans and Fretibacterium accounted mostly at the genus level, and genus Aeromonas showed an extremely low abundance (2.02%) on average. The fungal community was dominated by the phylum Ascomycota and Basidiomycota. At the genus level, the dominant OTUs included Mortierella, Geminibasidium and Fusarium. The analysis of core taxa included those above dominant genera and some low-abundance genera (>1%). The functional annotation of the bacterial community showed a close correlation with metabolism (34.8 ± 0.6%). Some fungal species were predicted as opportunistic human pathogens including Fusarium and Chaetomiaceae. CONCLUSIONS: The present study provides fundamental rationales for further studies of such issues as bacteria-fungi-host interactions, host fitness, potential pathogens, and infecting risks after leeching. It shall facilitate in-depth explorations on the safe utilization of leech therapy. SIGNIFICANCE AND IMPACT OF STUDY: Present paper is the first-ever exploration on microbiota of a prevalent Asian medicinal leech based on culture-independent technical. And it is also the first report of gut fungi community of medicinal leech. The diversity and composition of bacteria in P. manillensis was far different from that of the European leech. The main components and core OTUs indicate a particular gut environment of medicinal leech. Unknown bacterial and fungal species were also recovered from leech gut.
Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.
Summary
16S rRNA-based microbiome profiling of Poecilobdella manillensis identifying dominant Aeromonas, Bacteroidetes and Firmicutes communities — assesses zoonotic potential.
Why This Matters for Hirudotherapy
This study characterized gut bacterial and fungal communities of the Asian medicinal leech Poecilobdella manillensis through culture-independent sequencing of 18 samples, identifying 779/939 OTUs dominated by Bacteroidetes and Synergistetes (bacteria) and Ascomycota and Basidiomycota (fungi), with some fungal species predicted as opportunistic human pathogens including Fusarium and Chaetomiaceae. For hirudotherapy and ASH, this work is directly relevant because opportunistic infections remain a recognized risk of leech therapy, and characterizing the microbiome of a prevalent Asian medicinal leech species provides foundational data for assessing and mitigating these infection risks. The authors note the bacterial diversity of P. manillensis differs markedly from that of the European leech, suggesting safety considerations may vary by species. A key caveat is that this is a descriptive microbiological characterization study, not a clinical assessment of actual infection rates or patient outcomes after leeching.
Citation
Insights into gut microbiota communities of Poecilobdella manillensis, a prevalent Asian medicinal leech.
Meng F et al. · Journal of applied microbiology, 2022
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