In this task, you're given a paragraph from the research paper and your task is to generate a suitable title for the research paper based on the given paper. Under 100 words is a good title length.

2H phosphoesterases catalyze reactions on nucleotide substrates and contain two conserved histidine residues in the active site. Very limited information is currently available on the details of the active site and substrate/product binding during the catalytic cycle of these enzymes. We performed a comprehensive X-ray crystallographic study of mouse 2′,3′-cyclic nucleotide 3′-phosphodiesterase (CNPase), a membraneassociated enzyme present at high levels in the tetrapod myelin sheath. We determined crystal structures of the CNPase phosphodiesterase domain complexed with substrate, product, and phosphorothioate analogues. The data provide detailed information on the CNPase reaction mechanism, including substrate binding mode and coordination of the nucleophilic water molecule. Linked to the reaction, an open/close motion of the β5-α7 loop is observed. The role of the N terminus of helix α7-unique for CNPase in the 2H family-during the reaction indicates that 2H phosphoesterases differ in their respective reaction mechanisms despite the conserved catalytic residues. Furthermore, based on small-angle X-ray scattering, we present a model for the full-length enzyme, indicating that the two domains of CNPase form an elongated molecule. Finally, based on our structural data and a comprehensive bioinformatics study, we discuss the conservation of CNPase in various organisms.
Crystallographic Analysis of the Reaction Cycle of 2′,3′-Cyclic Nucleotide 3′-Phosphodiesterase, a Unique Member of the 2H Phosphoesterase Family

Toxoplasma gondii is a worldwide spread protozoan and is able to infect almost all warm-blood animals. No effective drugs are available clinically on toxoplasmosis. Chinese traditional herbal medicines have provided remedies for many health problems. There exists a possibility that Chinese herbs may provide protection against T. gondii. This work aims to assess the protective efficacy of combined Chinese herbs against T. gondii. We screened five herbal medicines that have different pharmacological effects and combined them into a prescription according to the traditional Chinese medicine compatibility principle. The drug potential and protective efficacy were evaluated through a mouse model by determining the survival time, the parasite load in blood and tissues, the change of cell proportions in blood and histological detection. The results showed that the survival time of mice in the 500 mg Chinese herbs group and sulfadiazine group was significantly longer than that of the PBS control group. Also the parasite load in blood and tissues of 500 mg Chinese herbs and sulfadiazine groups was significantly lower than that of PBS group at 7 days post infection (dpi), which was in accordance with the result of histological detection. Monocyte and neutrophil of infected mice were remarkably increased while lymphocyte was dramatically decreased compared to that of blank group at 7 dpi. The results demonstrated that the 500 mg dosage of our Chinese herbs could slow down the replication of T. gondii and prolong the survival time of mice and could be considered as possible candidate drug against toxoplasmosis.
Evaluation of potential anti-toxoplasmosis efficiency of combined traditional herbs in a mouse model *

In the present study, we have generated a murine monoclonal antibody (mAb) named Sal-06 by using the crude outer membrane protein preparation of Salmonella enteric subsp. enterica serovar Typhimurium ATCC 14028 strain as antigen. Sal-06mAb belonging to IgG1 isotype demonstrated broad cross-reactivity to standard and isolated strains of genus Salmonella and others such as Escherichia coli, Klebsiella pneumonia, and Proteus mirabilis. Cross-reactivity across several bacterial genera indicated that the epitopes reactive to Sal-06mAb are conserved among these members. Neutralizing effects of Sal-06mAb on Salmonella growth and survival was evaluated in vitro using bacteriostatic and bactericidal activity with and without complement and bacterial invasion inhibition assay. Sal-06mAb demonstrated a bacteriostatic effect on the growth of S. typhimurium ATCC 14028 strain which is both time and concentration (of mAb) dependent. It was also found that the bacterial growth inhibition was complement independent. When the bacterial cells were preincubated with Sal-06mAb, it reduced the adherence and invasion of bacterial cells into A549 epithelial cell line. This was confirmed by CFU count analysis, phase contrast, and fluorescence microscopy. Scanning electron microscope (SEM) imaging confirmed the antimicrobial effects of Sal-06mAb on S. typhimurium ATCC 14028. The development of broadly reactive and cross protective Sal-06mAb opens new possibilities for immunotherapy of sepsis caused by Gram-negative Enterobacteriaceae members.

Functional characterization of a broad and potent neutralizing monoclonal antibody directed against outer membrane protein (OMP) of Salmonella typhimurium

