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The Delta Smelt (Hypomesus transpacificus) is a small, semi-anadromous fish native to the San Francisco Bay-Delta Estuary and has been declared as critically endangered. Their olfactory biology, in particular, is poorly understood and a basic description of their sensory anatomy is needed to advance our understanding of the sensory ecology of species to inform conservation efforts to manage and protect them. We provide a description of the gross morphology, histological, immunohistochemical, and ultrastructural features of the olfactory rosette in this fish and discuss some of the functional implications in relation to olfactory ability. We show that Delta Smelt have a multilamellar olfactory rosette with allometric growth. Calretinin immunohistochemistry revealed a diffuse distribution of olfactory receptor neurons within the epithelium. Ciliated, microvillous and crypt neurons were clearly identified using morphological and immunohistochemical features. The olfactory neurons were supported by robust ciliated and secretory sustentacular cells. Although the sense of smell has been overlooked in Delta Smelt, we conclude that the olfactory epithelium has many characteristics of macrosmatic fish. With this study, we provide a foundation for future research into the sensory ecology of this imperiled fish.

Pulmonary alveolar proteinosis (PAP) is a disease of surfactant clearance in which functional abnormalities in alveolar macrophages lead to accumulation of surfactant within alveoli in mammals. Histologic examination of 6 avian autopsies, including 4 chickens, a turkey, and a cockatiel, revealed accumulation of hypereosinophilic densely arrayed lamellar material in the lungs that was magenta by periodic acid-Schiff stain and diastase resistant. Transmission electron microscopy of the proteinaceous material in 2 cases demonstrated alternating electron-dense and electron-lucent lamellae that formed whorls and had a regular periodicity of 6-14 nm, consistent with pulmonary surfactant. Given the anatomic differences between avian and mammalian lungs, we designated the presented condition "pulmonary proteinosis," which can be observed as both an incidental finding or, when severe, may be a contributing factor to death through respiratory failure.

The formation of different sized nanoliprotein particles (NLPs) by the interactions between apolipoproteins and phospholipids is discussed. The selection of apolipoprotein used in an assembly causes the size and homogenity of the final nanostructure.

Microcapsules containing subfemtoliter volumes of n-hexadecane (HD) within a 4-40 nm thick shell of poly(alkyl methacrylates) were prepared. The size of the HD drop was varied between 50 and 140 nm. The alkyl substituents on the methacrylate monomer were varied to alter the surface tension between the HD and the polymer shell in order to investigate the effects of surface tension on the freezing point of the HD. The size dependence of the supercooling as predicted by the G-T equation was not observed in our systems. An effect on the magnitude of supercooling with variation in the side chains was observed, where freezing the HD in capsules with bulkier side chains requires a greater magnitude of supercooling. This is in agreement with the increased hydrophobic character of the polymers and also correlates with the decrease in glass transition temperature of the polymer. We also observed aging of the capsules, which could be accelerated by heating.

Membrane-associated proteins and protein complexes account for approximately a third or more of the proteins in the cell (1, 2). These complexes mediate essential cellular processes; including signal transduc-tion, transport, recognition, bioenergetics and cell-cell communication. In general, membrane proteins are challenging to study because of their insolubility and tendency to aggregate when removed from their protein lipid bilayer environment. This chapter is focused on describing a novel method for producing and solubilizing membrane proteins that can be easily adapted to high-throughput expression screening. This process is based on cell-free transcription and translation technology coupled with nanolipoprotein par ticles (NLPs), which are lipid bilayers confined within a ring of amphipathic protein of defined diameter. The NLPs act as a platform for inserting, solubilizing and characterizing functional membrane proteins. NLP component proteins (apolipoproteins), as well as membrane proteins can be produced by either traditional cell-based or as discussed here, cell-free expression methodologies.

Here we present modeling and NMR spectroscopic evidence that the function of a Yersinia pestis pMT1 plasmid protein, designated as orf38, is most likely a glutamine binding protein. The modeling was homology-based at a very low level of sequence identity ( approximately 16%) and involved structural comparison of multiple templates, as well as template-substrate interaction analyses. Transferred nuclear Overhauser and saturation transfer difference experiments were used to characterize the binding of sugars and amino acids to orf38. The identification and characterization of an unknown protein function using the strategy presented here has applicability to a variety of research areas, including functional genomics and proteomics efforts.