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

Campylobacter jejuni remains one of the major gut pathogens of our time. Its zoonotic nature and wide-spread distribution in industrialized countries calls for a quick and reliable diagnostic tool. Antibody-based detection presents a suitable means to identify pathogenic bacteria. However, the knowledge about immunodominant targets is limited. Thus, an approach is presented, which allows for the rapid screening of numerous cDNA derived expression clones to identify novel antigens. The deeper understanding of immunodominant proteins assists in the design of diagnostic tools and furthers the insight into the bacterium's pathogenicity as well as revealing potential candidates for vaccination. We have successfully screened 1536 clones of an expression library to identify 22 proteins that have not been described as immunodominant before. After subcloning the corresponding 22 genes and expression of full-length proteins, we investigated the immunodominant character by microarrays and ELISA. Subsequently, seven proteins were selected for epitope mapping. For cj0669 and cj0920c linear epitopes were identified. For cj0669, specificity assays revealed a specific linear epitope site. Consequently, an eleven amino acid residue sequence TLIKELKRLGI was analyzed via alanine scan, which revealed the glycine residue to be significant for binding of the antibody. The innovative approach presented herein of generating cDNAs of prokaryotes in combination with a microarray platform rendering time-consuming purification steps obsolete has helped to illuminate novel immunodominant proteins of C.jejuni. The findings of a specific linear epitope pave the way for a plethora of future research and the potential use in diagnostic applications such as serological screenings. Moreover, the current approach is easily adaptable to other highly relevant bacteria making it a formidable tool for the future discovery of antigens and potential biomarkers. Consequently, it is desirable to simplify the identification of structural epitopes, as this would extend the spectrum of novel epitopes to be detected.
Rapid Identification of Novel Immunodominant Proteins and Characterization of a Specific Linear Epitope of Campylobacter jejuni

The interferon (IFN)-inducing capacities of intact NDV virions, /3-propiolactone-inactivated particles and several structural components were compared, using human PBML as the IFN producing cells. Intact and inactivated virions as well as the nucleocapsid fraction did not differ significantly in their IFN-inducing capacity. In contrast, genomic RNA as well as M protein fraction and envelopes induced IFN titres to a level of about 10% of those achieved with virions. NDV-induced IFN production could be blocked specifically by incubation with polyclonal anti-NDV-monoclonal antibodies (mAbs) and with two of three anti-HN-mAbs, but not with anti-NDV-mAbs directed against the F, M or NP protein. In addition, IFN induction by fixed MDBK cells, expressing NDV surface proteins after infection with NDV Ulster, was inhibited by one of two anti-F-mAbs. The results suggest that the induction of IFN synthesis in human PBML is a complex process involving not only the HN protein but also the uncleaved F protein precursor, a component of the M protein fraction and -once having entered the cell -the genomic RNA.

More than one component of the Newcastle disease virus particle is capable of interferon induction