The localization of tightly bound cardiolipin in cytochrome oxidase

One to two molecules of tightly bound cardiolipin are associated with resolved fractions of cytochrome oxidase containing subunits I to III or I to IV. Large scale isolation of subunits I to IV indicates the presence of approximately 0.5 molecule of cardiolipin per molecule of subunit I. Lipoprotein staining of sodium dodecyl sulfate/urea/acrylamide gels of cytochrome oxidase support the findings that subunit I is a lipoprotein. The resistance of this tightly bound cardiolipin to organic solvent extraction suggests a specific association of some tenacity with the protein.     

Natal recruitment and adult retention in a population of nine-banded armadillos

Nine-banded armadillosDasypus novemcinctus Linnaeus, 1758 are interesting in part because (a) they give birth to litters of genetically identical quadruplets, and (b) the species’ range has expanded rapidly throughout the southern United States during the last 150 years, suggesting substantial dispersal of individuals. Using data from 7 field seasons between 1992 and 1999, we examined the extent of juvenile recruitment and retention of adults in a population of armadillos from northern Florida. There were no sex differences in the likelihood of recruitment or most attributes of male and female recruits at any age. In the few cases where more than one littermate was recruited into the population, siblings were significantly more widely dispersed as adults than they were as juveniles, thus limiting opportunities for interaction among clonal siblings. There was some evidence that recruits ranged more widely than other individuals, suggesting recruits may have been searching for suitable sites to establish themselves. Recruits were heavier than non-recruits as both juveniles and yearlings, which may have aided in establishing a home range, but recruits were lighter than other animals as adults. Overall, slightly less than 50% of armadillos first captured as adults were never seen in a subsequent year, suggesting these individuals may have been transients. However, some adults remained in the population for multiple years, moving very little from the area where they were first sighted. As with recruits, there were no sex differences in the likelihood of adults being retained in the population nor in the attributes of retained males and females. Retained animals exhibited more extensive anatomical damage and moved farther between successive sightings within years than did non-residents. Adults were more likely to be retained in the population than juveniles were to be recruited, and retained adults were older, heavier, and exhibited more extensive anatomical damage than did recruits. Our data seem to indicate a population characterized by limited recruitment of juveniles (particularly of clonemates) and an adult population exhibiting considerable turnover from year to year, but with a core of individuals who are long-term residents.     

Alteration of the Pathogenicity of Pasteurella pneumotropica for the Murine Lung Caused by Changes in Pulmonary Antibacterial Activity

Pasteurella pneumotropica is a potential pulmonary pathogen in mice. In healthy animals, this organism was killed rapidly by the normal function of the intrapulmonary phagocytic defense mechanisms. Impairment of this bactericidal activity by the acute renal failure of nephrectomy resulted in multiplication of the Pasteurella in the lung, both when the animals were nephrectomized first and then infected, and when the animals were infected first and nephrectomized several hours after the infection. The study demonstrates that the pathogenicity of the Pasteurella organisms is governed by the functional state of these pulmonary antibacterial mechanisms.     

Regulation of human T cell leukemia virus expression

Retroviruses of the type C morphology have been implicated in a wide variety of diseases in animals and humans. The human T cell leukemia viruses types I (HTLV-I) and II (HTLV-II), the prototypic human-type C retroviruses, have been identified as the causative agents of some forms of human leukemia and neurological disorders. The genetic structure and regulation of the HTLVs are more complex than their avian and murine leukemia virus counterparts. In addition to the gag, pol, and env genes that encode the characteristic virion proteins of all replication competent retroviruses, the genomes of HTLV encode the non-structural proteins, Tax and Rex, which are required for regulating viral gene expression. To understand what appears to be a complex mechanism of disease induction by HTLV, elucidating the regulation and function of the viral gene products and the interaction of these products with each other, as well as with cellular factors, will be critical. This review focuses primarily on regulation of HTLV gene expression in the infected human T lymphocyte, but also discusses analogous gene regulation by the human immunodeficiency virus (HIV). It concentrates specifically on the role these gene products play in virus replication and, ultimately, pathogenesis.     

Detection and quantification of patulin and griseofulvin by high pressure liquid chromatography in different strains of Penicillium griseofulvum Dierckx

Patulin and griseofulvin production by twelve strains ofPenicillium griseofulvum Dierckx, eleven of which were isolated from pistachio (Pistacia vera) nuts and the other was supplied by the Spanish Collection of Type Culture, was investigated. Six strains of the eleven isolated had ability to produce patulin and griseofulvin in Yes medium. All the strains studied had no ability to produce patulin in Wickerham medium. Griseofulvin production was significant in both media but higher in Wickerham. These metabolites were separated and determined in the chloroform extracts of cultures by high performance liquid chromatography with ultraviolet detection. The best conditions were: acetonitrile — water (45∶55) as mobile phase, a flow rate of 2.0 mL/min and a μ Bondapack C₁₈ column.