Biochemical Characterization of Hyaluronate Lyase CpHly8 from an Intestinal Microorganism Clostridium perfringens G1121.

Hyaluronic acid (HA) is an important component of extracellular matrices (ECM) and a linear polysaccharide involved in various physiological and pathological processes within the biological system. Several pathogens exploit HA degradation within the extracellular matrix to facilitate infection. While many intestinal microorganisms play significant roles in HA utilization in the human body, there remains a scarcity of related studies. This paper addressed this gap by screening intestinal microorganisms capable of degrading HA, resulting in the isolation of Clostridium perfringens G1121, which had been demonstrated the ability to degrade HA. Subsequent genome sequencing and analysis of C. perfringens G1121 revealed its utilization of the polysaccharide utilization loci of HA (PUL), which was obtained by horizontal gene transfer. The PUL contains a sequence encoding a hyaluronic acid-specific degradation enzyme designated CpHly8, belonging to polysaccharide lyase family 8. The specific activity of CpHly8 towards HA was 142.98 U/mg, with the optimum reaction temperature and pH observed at 50℃ and 6.0, respectively. The final product of HA degradation by CpHly8 was unsaturated hyaluronic acid disaccharide. Moreover, subcutaneous diffusion experiments with trypan blue in mice revealed that CpHly8 effectively promoted subcutaneous diffusion and sustained its effects long-term, suggesting its potential application as an adjunct in drug delivery. Overall, our study enriches our understanding of intestinal microbial degradation of HA, provides new evidence for horizontal gene transfer among intestinal microorganisms, and confirms that CpHly8 is a promising candidate for intestinal microbial hyaluronidase.