Dopamine-induced sulfatase and its regulator are required for Salmonella enterica serovar Typhimurium pathogenesis

Purification, Characterization, and Structural Studies of a Sulfatase from Pedobacter yulinensis

Sulfatases are ubiquitous enzymes that hydrolyze sulfate from sulfated organic substrates such as carbohydrates, steroids, and flavones. These enzymes can be exploited in the field of biotechnology to analyze sulfated metabolites in humans, such as steroids and drugs of abuse. Because genomic data far outstrip biochemical characterization, the analysis of sulfatases from published sequences can lead to the discovery of new and unique activities advantageous for biotechnological applications. We expressed and characterized a putative sulfatase (PyuS) from the bacterium Pedobacter yulinensis. PyuS contains the (C/S)XPXR sulfatase motif, where the Cys or Ser is post-translationally converted into a formylglycine residue (FGly). His-tagged PyuS was co-expressed in Escherichia coli with a formylglycine-generating enzyme (FGE) from Mycobacterium tuberculosis and purified. We obtained several crystal structures of PyuS, and the FGly modification was detected at the active site. The enzyme has sulfatase activity on aromatic sulfated substrates as well as phosphatase activity on some aromatic phosphates; however, PyuS did not have detectable activity on 17α-estradiol sulfate, cortisol 21-sulfate, or boldenone sulfate.

SdsA1, a secreted sulfatase, contributes to the in vivo virulence of Pseudomonas aeruginosa in mice

Mucin is a glycoprotein that is the primary component of the mucus overlaying the epithelial tissues. Because mucin functions as a first line of the innate immune system, Pseudomonas aeruginosa appears to require interaction with mucin to establish infection in the host. However, the interactions between P. aeruginosa and mucin have been poorly understood. In this study, using in vivo expression technology (IVET), we attempted to identify mucin-inducible promoters that are likely to be involved in the establishment of P. aeruginosa infection. The IVET analysis revealed that the genes encoding glycosidases, sulfatases, and peptidases that are thought to be required for the utilization of mucin as a nutrient are present in 13 genes downstream of the identified promoters. Our results indicated that, among them, sdsA1 encoding a secreted sulfatase plays a central role in the degradation of mucin. It was then demonstrated that disruption of sdsA1 leads to a decreased release of sulfate from mucin and sulfated sugars. Furthermore, the sdsA1 mutant showed a reduction in the ability of mucin gel penetration and an attenuation of virulence in leukopenic mice compared with the wild-type strain. Collectively, these results suggest that SdsA1 plays an important role as a virulence factor of P. aeruginosa.

Advances in Gut Microbiota of Viral Hepatitis Cirrhosis

Although gut dysbiosis appears in 20%-75% of cirrhotic patients, there are limited data on microbiota profiles in viral hepatitis cirrhotics and its role in progression to cirrhosis. Further understanding on the relationship between gut dysbiosis and cirrhosis presents a unique opportunity in not only predicting the development of cirrhosis but also discovering new therapies. Recent advances have been made on identifying unique microbiota in viral hepatitis cirrhotics and adopting the microbiota index to predict cirrhosis. Therapeutic intervention with microbiome-modulating has been explored. Cirrhosis from viral infection has unique bacterial or fungal profiles, which include increased numbers of Prevotella, Streptococcus, Staphylococcaceae, and Enterococcus, as well as decreased Ruminococcus and Clostridium. In addition, the gut microbiota can stimulate liver immunity, effectively helping hepatitis virus clearance. In clinical settings, CDR, GDI, Basidiomycota/Ascomycota, specific POD, and so forth are efficient microbiota indexes to diagnose or prognosticate cirrhosis from viral hepatitis. FMT, probiotics, and prebiotics can restore microbial diversity in cirrhotic patients with viral hepatitis, decrease ammonia serum or endotoxemia levels, prevent complications, reduce rehospitalization rate, and improve prognosis. Cirrhotics from viral hepatitis had unique bacterial or fungal profiles, associated with specific metabolic, immune, and endocrinological statuses. Such profiles are modifiable with medical treatment. The role of gut archaea and virome, implementation of FMT, microbiota metabolites as adjuvant immunotherapy, and microbiota indexes for prognostication deserve attention.