A comprehensive review on microbial hyaluronan-degrading enzymes: from virulence factors to biotechnological tools.

Hyaluronan (HA), a natural high molecular weight polysaccharide, has extensive applications in cosmetology and medical treatment. Hyaluronan-degrading enzymes (Hyals) act as molecular scissors that cleave HA by breaking the glucosidic linkage. Hyals are present in diverse organisms, including vertebrates, invertebrates and microorganisms, and play momentous roles in biological processes.

Engineering protein translocation and unfolded protein response enhanced human PH-20 secretion in Pichia pastoris.

Hyaluronidases catalyze the degradation of hyaluronan (HA), which is finding rising applications in medicine, cosmetic, and food industries. Recombinant expression of hyaluronidases in microbial hosts has been given special attention as a sustainable way to substitute animal tissue-derived hyaluronidases. In this study, we focused on optimizing the secretion of hyaluronidase from Homo sapiens in Pichia pastoris by secretion pathway engineering.

High-level expression and characterization of a highly active hyaluronate lyase HylC with significant potential in hyaluronan oligosaccharide preparation.

Hyaluronate lyases (HA lyases) have been proved to distribute widely among microorganisms, with large potential in hyaluronan processing. Here, a highly active HA lyase HylC from Citrobacter freundii strain Cf1 is reported. HylC was expressed in Escherichia coli BL21(DE3) under the regulation of T7 promoter, and purified to electrophoretic homogeneity for enzymatic characterization, which suggested its suitable thermo- and pH stability under 45 °C and pH rang of 4-8, and high halotolerancy in 1.

Insights into the source, mechanism and biotechnological applications of hyaluronidases.

It has long been found that hyaluronidases exist in a variety of organisms, playing their roles in various biological processes including infection, envenomation and metabolic regulation through degrading hyaluronan. However, exploiting them as a bioresource for specific applications had not been extensively studied until the latest decades. In recent years, new application scenarios have been developed, which extended the field of application, and emphasized the research value of hyaluronidase.

Sensory involvement in the SOD1-G93A mouse model of amyotrophic lateral sclerosis.

A subset of patients of amyotrophic lateral sclerosis (ALS) present with mutation of Cu/Zn superoxide dismutase 1 (SOD1), and such mutants caused an ALS- like disorder when expressed in rodents. These findings implicated SOD1 in ALS pathogenesis and made the transgenic animals a widely used ALS model. However, previous studies of these animals have focused largely on motor neuron damage.