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.

[EX Q]: We tested the role of the "spring-loaded" conformational change in the fusion mechanism of the influenza hemagglutinin (HA) by assessing the effects of 10 point mutants in the region of high coiled-coil propensity, HA2 54-81. The mutants included proline substitutions at HA2 55, 71, and 80, as well as a double proline substitution at residues 55 and 71. Mutants were expressed in COS or 293T cells and assayed for cell surface expression and structural features as well as for their ability to change conformation and induce fusion at low pH. We found the following: Specific mutations affected the precise carbohydrate structure and folding of the HA trimer. All of the mutants, however, formed trimers that could be expressed at the cell surface in a form that could be proteolytically cleaved from the precursor, HA0, to the fusion-permissive form, HA1-S-S-HA2. All mutants reacted with an antibody against the major antigenic site and bound red blood cells. Seven out of ten mutants displayed a wild-type (wt) or moderately elevated pH dependence for the conformational change. V55P displayed a substantial reduction ( 60-80%) in the initial rate of lipid mixing. The other single mutants displayed efficient fusion with the same pH dependence as wt-HA. The double proline mutant V55P/ S71P displayed no fusion activity despite being well expressed at the cell surface as a proteolytically cleaved trimer that could bind red blood cells and change conformation at low pH. The impairment in fusion for both V55P and V55P/S71P was at the level of outer leaflet lipid mixing. We interpret our results in support of the hypothesis that the spring-loaded conformational change is required for fusion. An alternate model is discussed.
[EX A]: Specific Single or Double Proline Substitutions in the "Spring-loaded" Coiled-Coil Region of the Influenza Hemagglutinin Impair or Abolish Membrane Fusion Activity

[EX Q]: Coronaviruses strains 229E and OC43 have been associated with various respiratory illnesses ranging from the self-resolving common cold to severe pneumonia. Although chronic underlying conditions are major determinants of severe respiratory virus infections, few data about coronavirus-related pneumonia in immunocompromised patients are available. Here we report 2 well-documented cases of pneumonia related to coronavirus 229E, each with a different clinical presentation. Diagnosis was made on the basis of viral culture and electron microscopy findings that exhibited typical crown-like particles and through amplification of the viral genome by reverse transcriptase-polymerase chain reaction. On the basis of this report, coronaviruses should be considered as potential causative microorganisms of pneumonia in immunocompromised patients.
[EX A]: Coronavirus 229E-Related Pneumonia in Immunocompromised Patients

[EX Q]: The interdisciplinary field of research on biosystems at the nanoscale involving physical sciences, molecular engineering, biology, biotechnology, and medicine supplements the knowledge of synthesizing new drugs, targeted delivery, regenerative medicine, and neuromorphic engineering forms the booming research in the present society. The present chapter deals with the role of nanoparticles in modern molecular biology. This is an interesting area of research that creates great impact on the healthcare of the society. The prime focus is to give the reader a historic background of nanomaterial application in biology and medicine. We have also provided the overview of most recent developments in this field leading to discussion of hard road to commercialization.
[EX A]:
6 Nanoparticles as Precious Stones in the Crown of Modern Molecular Biology