American Society of Hirudotherapy

Temperature-controlled molecular weight of hyaluronic acid produced by engineered Bacillus subtilis

Biotechnology paper published in Biotechnology Letters (2020)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: In vitro / laboratoryDrug DevelopmentGenomics & ProteomicsLi Y et al. · Biotechnology Letters, 2020

Abstract

To produce high-, medium- and low-molecular-weight hyaluronic acid (HA) at different temperatures using engineered Bacillus subtilis expressing hyaluronidase (HAase) from leech. By overexpressing the HAase gene hya in the HA-producing strain WmB using temperature-sensitive plasmid pKSV7, the engineered strain WmB-PYh produced HA with different molecular weights (8.61 kDa at 32 °C, 0.615 MDa at 42 °C, and 6.19 MDa at 47 °C). In this study, the molecular weight of HA was regulated by using leech HAase expressed from a temperature-sensitive plasmid. We thus obtained different molecular weight HAs by using a single bacterial strain at different culture temperatures.

Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.

Publication typeJournal Article
Indexed MeSH termsAnimalsBacillus subtilisHyaluronic AcidHyaluronoglucosaminidaseLeechesMetabolic EngineeringMolecular WeightRecombinant ProteinsTemperature

Summary

Engineered Bacillus subtilis expressing leech hyaluronidase (HAase) on a temperature-sensitive plasmid produces hyaluronic acid of different molecular weights (8.61 kDa at 32°C, 0.615 MDa at 42°C, 6.19 MDa at 47°C).

Why This Matters for Hirudotherapy

This metabolic engineering study produced hyaluronic acid (HA) of different molecular weights using engineered Bacillus subtilis expressing a leech-derived hyaluronidase gene (hya) via a temperature-sensitive plasmid, achieving HA of 8.61 kDa at 32°C, 0.615 MDa at 42°C, and 6.19 MDa at 47°C from a single bacterial strain. The leech hyaluronidase serves as a molecular tool for tunable HA degradation in an industrial biotechnology context. The relevance to ASH is limited and indirect: the study characterizes a leech-derived enzyme but applies it in microbial fermentation rather than in any therapeutic, pharmacological, or hirudotherapy setting. No leeches, leech therapy, or clinical applications are involved, and the study's contribution is confined to bioprocess engineering leveraging a leech enzyme gene.

Citation

Temperature-controlled molecular weight of hyaluronic acid produced by engineered Bacillus subtilis.

Li Y et al. · Biotechnology Letters, 2020

DOI

Added to ASH library: May 27, 2026 · Site last updated: June 18, 2026

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