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Background: Disinfectant products are used frequently on environmental surfaces (e.g. medical equipment, countertops, patient beds) and patient care equipment within healthcare facilities. The purpose of this study was to assess the risk of cross-contamination of Staphylococcus aureus and Pseudomonas aeruginosa during and after disinfection of predetermined surface areas with ready-to-use (RTU) pre-wetted disinfectant towelettes. Methods: This study tested six disinfectant towelette products against S. aureus ATCC CRM-6538 and P. aeruginosa strain ATCC-15442 on Formica surfaces. Each disinfectant was evaluated on a hard nonporous surface and e cacy was measured every 0.5 m 2 using a modi ed version of EPA MLB SOP-MB-33 to study the risk of cross-contamination. Results: We found that all of the wipes used in this study transferred P. aeruginosa and S. aureus from an inoculated surface to previously uncontaminated surfaces. Disinfectant towelettes with certain chemistries also retained a high level of viable bacteria after disinfection of the surface area. The crosscontamination risk also varied by product chemistry and bacterial strain. Conclusion: Disinfectant wipes can cross-contaminate hard nonporous surfaces and retain viable bacterial cells post-disinfection, especially over larger surface areas. This highlights a need to further investigate the risk disinfectant wipes pose during and post-disinfection and guidance on maximum surface areas treated with a single towelette.

The cAMP-protein kinase A (PKA) pathway, important in neuronal signaling, is regulated by molecules that bind and target PKA regulatory subunits. Of four regulatory subunits, RI␤ is most abundantly expressed in brain. The RI␤ knockout mouse has defects in hippocampal synaptic plasticity, suggesting a role for RI␤ in learning and memory-related functions. Molecules that interact with or regulate RI␤ are still unknown. We identified the neurofibromatosis 2 tumor suppressor protein merlin (schwannomin), a molecule related to the ezrin-radixin-moesin family of membrane-cytoskeleton linker proteins, as a binding partner for RI␤. Merlin and RI␤ demonstrated a similar expression pattern in central nervous system neurons and an overlapping subcellular localization in cultured hippocampal neurons and transfected cells. The proteins were coprecipitated from brain lysates by cAMP-agarose and coimmunoprecipited from cellular lysates with specific antibodies. In vitro binding studies verified that the interaction is direct. The interaction appeared to be under conformational regulation and was mediated via the ␣-helical region of merlin. Sequence comparison between merlin and known PKA anchoring proteins identified a conserved ␣-helical PKA anchoring protein motif in merlin. These results identify merlin as the first neuronal binding partner for PKA-RI␤ and suggest a novel function for merlin in connecting neuronal cytoskeleton to PKA signaling.

Helicobacter pylori possesses a gene (HP0326/JHP309) homologous to neuA of other bacteria, encoding a cytidyl monophosphate-N-acetylneuraminic acid synthetase-homologous enzyme in its N-terminal portion. We analysed the function of this gene, which is controlled by a flagellar class 2 sigma(54) promoter, in flagellar biosynthesis. HP0326/JHP309 actually represents a bicistronic operon consisting of a neuA and a flmD-like putative glycosyl transferase gene. An isogenic flmD mutant synthesized basal bodies but no filaments, was non-motile, and expressed severely reduced amounts of a FlaA flagellin of reduced molecular mass. FlaA flagellin was found to be glycosylated in its exported form within the flagellar filament, but not inside the cytoplasm. Glycosylated FlaA was not detectable in the flmD mutant. Together with other genes in the H. pylori genome, a proposed function of the neuA/flmD gene products could be to provide a pathway for glycosylation of flagellin and other extracytoplasmic molecules during type III secretion.