Rat Sertoli and spermatogenic cells express a similar gene, and its product is antigenically related to an outer dense fiber-associated protein.

We have previously reported that a heterodimeric protein secreted by rat Sertoli cells is antigenically related to a protein associated with outer dense fibers of the sperm tail. Therefore, we have explored the possibility that Sertoli and spermatogenic cells express a similar gene encoding a homologous protein. A Sertoli cell heterodimeric protein cDNA probe recognizes specific mRNA in pachytene and round spermatids fractionated by centrifugal elutriation; however, this specific mRNA was less prominent than in cultured Sertoli cells. In agreement with these observations, in situ hybridization experiments show that Sertoli cells are predominantly engaged in active heterodimeric protein mRNA synthesis, while meiotic prophase spermatocytes and spermatids also show significant but less abundant specific mRNA. Immunoblotting experiments demonstrate that, while Sertoli cells synthesize a heterodimeric protein consisting of two disulfide-linked components with molecular masses of 45 and 35 kD, both primary spermatocytes and round spermatids synthesize single 30 kD monomers not associated by disulfide linkage but recognized by antisera to Sertoli cell heterodimeric protein. Immunoblotting and immunogold electron microscopic studies show that antisera to Sertoli cell heterodimeric protein recognize a protein associated with outer dense fibers. This immunoreactivity was abolished by a 5-min pronase treatment, without affecting the integrity of outer dense fibers. Results of this study and previous studies demonstrate that both Sertoli and spermatogenic cells express a similar gene and that an antigenically related product encoded by this gene becomes associated with outer dense fibers during their assembly at spermiogenesis.     

Intraspecific variation in reproductive physiology and egg quality in the European Starling Sturnus vulgaris

Egg mass shows large intraspecific variation in birds and is repeatable within individuals. The mechanisms underlying this variation are unknown. We hypothesized that measures of egg quality (the mass of yolk protein, yolk lipid, and albumen protein) would be positively correlated with the plasma pools of the yolk precursor vitellogenin, and the masses of the oviduct, metabolic machinery (liver, heart, lungs, kidneys, gizzard, small intestine and pancreas), and endogenous stores of protein and lipid. We tested these predictions in European Starlings Sturnus vulgaris collected at the peak of egg production effort. In contrast to our predictions, both yolk protein and yolk lipid were negatively correlated with plasma vitellogenin levels. Albumen protein was positively related to oviduct mass, but other aspects of body composition failed to explain variation in egg quality. Hence, while we observed correlations between egg composition and peripheral systems (circulating precursor pools and the oviduct), we found no evidence that egg quality is determined by more general processes, i.e., the supply and processing of nutrients.     

Detection of asymptomatic herpes simplex virus infections after vaccination.

Twenty-two volunteers seronegative for antibodies to herpes simplex virus (HSV) were enrolled in a trial to determine tolerance and immunogenicity of an HSV-2 glycoprotein subunit vaccine. Vaccine was administered at days 0, 28, and 140, and sera were obtained on days 0, 7, 14, 21, 28, 35, 49, 56, 140, 147, and 365 for determination of HSV neutralizing antibody activity and antibody-dependent cell cytotoxicity (ADCC). Sera were also tested by immunoprecipitation of radiolabeled HSV-2-infected cell proteins and polyacrylamide gel electrophoresis to identify the viral proteins which elicited antibody responses in vaccine recipients. After vaccination two male volunteers presented with atypical first-episode genital herpes: patient 1 with a culture-negative genital lesion at day 53 and patient 3 with urethritis at day 68. Seroconversion to wild-type viral proteins not present in the vaccine was detectable by radioimmunoprecipitation-polyacrylamide gel electrophoresis within 10 days in both patients. Two additional volunteers, one a sex contact of patient 1, seroconverted asymptomatically to nonvaccine proteins during the trial. All four vaccine breakthrough patients were indistinguishable from the other volunteers in the time required to develop neutralizing and ADCC antibodies, in the titer of these antibodies, and the time to seroconversion to gB and gD vaccine proteins. However, only one of the four breakthrough patients had antibodies to g80 (a complex of gC-2 and gE) after vaccination as compared with 15 of the other 18 volunteers (P = 0.05). Neither neutralizing antibody nor ADCC titers consistently identified acquisition of wild-type viral infection; therefore, protein-specific serologies were required to detect wild-type antibodies in these four patients. These data underscore the importance of using serologic assays which will distinguish naturally acquired infection from the immune response to vaccination.     

Bacterial siderophores : structure and NMR assignment of pyoverdins Pa,siderophores ofPseudomonas aeruginosa ATCC 15692

Summary In iron-deficient conditions,Pseudomonas aeruginosa ATCC 15692 synthesizes two major siderophores, pyoverdins Pa and pyoverdin Pa B. Two other compounds, pyoverdin Pa A (occurring from hydrolysis of pyoverdin Pa during the culture) and pyoverdin Pa C (occurring artifactually during the purification procedure) were also isolated. All these compounds possess the same partly cyclic peptide chain wherel-Orn(OH · HCO) isN -formyl,N -hydroxy-l-ornithine. The chain is bound to a chromophore derived from 2,3-diamino-6,7-dihydroxyquinoline and having the (S) configuration. The four pyoverdins differ only in the acyl substituent bound to the nitrogen atom bound to carbon C3 of the chromophore. This is succinamide (pyoverdin Pa), succinic acid (pyoverdin Pa A), methyl succinate (pyoverdin Pa C) and 2-oxoglutaric acid (pyoverdin Pa B). The complete¹H- and¹³CNMR assignments, using two-dimensional total correlation NMR spectroscopy (TOCSY) and rotating-frame Overhauser enhancement spectroscopy (ROESY) procedures, as well as¹H-¹³C correlations, are reported. The complete sequence of the peptide using CH-NH correlations was achieved by NMR and confirmed the partly cyclic structure earlier reported using fast-atom-bombardment mass spectrometry (FAB-MS) on the siderophores and their dansylated fragments [Briskot G, Taraz K, Budzikiewicz H (1989)Liebigs Ann Chem: 375–384]. The use of these NMR procedures appears to be a tool of choice and a complementary approach to FAB-MS in the structure determination of some complex pyoverdins.Abbreviations Ser serine - Arg arginine - Thr ethreonine - Lys lysine - OHOrn N -hydroxyornithine - Chr chromophore