A cDNA clone derived from sporulated oocysts of Eimeria tenella and encoding the expression product GX3262 was identified using a monoclonal antibody (12-09) raised against Eimeria acervulina sporozoites. The cDNA fragment containing the coccidial antigen gene was cloned in bacteriophage lambda gtl 1, transferred to a plasmid, and introduced into Escherichia coli for analysis of the gene products. The strain carrying the plasmid produced GX3262 as part of a fusion protein consisting of the first 1,006 amino acids of E. coli

In apparent contrast to most other tissues, the ocular lenses in vertebrates show striking differences in protein composition between taxa, most notably in the recruitment of different enzymes as major structural proteins. This variability appears to be the result ofat least partially neutral evolutionary processes, although there is also evidence for selective modification in molecular structure. Here we describe a bird, the chimney swift (Chaetura pelagica), that lacks 8-crystallin/ argininosuccinate lyase, usually the major crystallin of avian lenses. Clearly, 6-crystallin is not specifically required for a functionally effective avian lens. Furthermore the lens composition of the swift is more similar to that of the related hummingbirds than to that of the barn swallow (Hirundo rustica), suggesting that phylogeny is more important than environmental selection in the recruitment of crystallins. However differences in e-crystallin/lactate dehydrogenase-B sequence between swift and hummingbird and other avian and reptilian species suggest that selective pressures may also be working at the molecular level. These differences also confirm the close relationship between swifts and hummingbirds.In many vertebrate species recruited enzymes comprise a large fraction of the crystallins, the soluble, structural proteins of the lens (1, 2). This phenomenon, a form of genesharing or protein multifunctionality, has wide implications for the processes of protein evolution and the mechanisms of differential gene expression. It also raises questions about the origins and roles of specific crystallins, why particular proteins were recruited as crystallins, and how important they are for correct lens development and function. Here we show that the expression of S-crystallin/argininosuccinate Iyase (ASL) (3) varies widely in avian lenses and appears to be more dependent on phylogeny than on any obvious functional or environmental selection. We have shown previously that two S-crystallin genes are abundantly expressed in the embryonic duck lens (refs. 4, 5; G.W. and J.P., unpublished data), whereas only one gene contributes significantly to 8-crystallin in the chicken lens (6, 7). Now we describe an avian species, the chimney swift (Chaetura pelagica), a fast-flying insectivore, that has no detectable lens expression of 8-crystallin at all, although its lens does contain abundant E-crystallin/lactate dehydrogenase B (LDH-B) (8). The hummingbirds are thought to be most closely related to the swifts in spite of marked superficial differences, most notably in feeding behavior. We have found that Anna's hummingbird (Calypte anna) does express detectable 8-crystallin but at a rather low level and also has extremely abundant e-crystallin. In contrast, the more distantly related barn swallow (Hirundo rustica), another fast-flying insectivore with similar feeding habits to the swift, has a quite different lens crystallin composition, with a more typical level of 6-crystallin and low or absent e-crystallin. Surprisingly, moreover...

Rice glutelin protein was extracted from defatted medium-grain rice by alkali extraction followed by acid precipitation. Extracted glutelin was hydrolyzed with Pronase E, a bacterial protease, and the functional properties of hydrolysates were evaluated. Nitrogen solubility of pronase-treated glutelin protein increased from pH 2 to pH 12. Similarly, foaming and emulsion properties of hydrolyzed protein also showed improved characteristics. The emulsion activity, expressed as the turbidity of diluted emulsions, was significantly greater (P ≤ 0.05) for hydrolyzed samples. However, turbidity for all samples decreased with increased homogenization time, indicating a decrease in the volume of dispersed oil. There were significant changes in apparent viscosity as a function of shear rate, with viscosity decreasing with increasing shear rate. The viscosity of dispersions of all hydrolyzed samples was significantly lower than that of the native sample at all shear rates tested. Enzymatic hydrolysis of rice endosperm storage glutelin proteins appeared to improve the functional characteristics of the hydrolyzed proteins.

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