SC1/hevin. An extracellular calcium-modulated protein that binds collagen I

SC1, a member of the BM-40 family of extracellular matrix proteins, was recombinantly expressed in a eukaryotic expression system. The full-length protein as well as truncated versions were purified to homogeneity under non-denaturing conditions. Matrix-assisted laser desorption ionization time-of-flight mass spectrometry of full-length SC1 revealed a mass of 87.8 kDa of which 16.8 kDa is contributed by posttranslational modifications. In electron microscopy, after negative staining, SC1 was revealed as a globule attached to a thread-like structure. A calcium dependence of the SC1 conformation could be demonstrated by fluorescence spectroscopy. In the extracellular matrix of cultured osteosarcoma cells SC1 was found associated with collagen I-containing fibrils, and binding of SC1 to reconstituted collagen I fibrils could be demonstrated by immunogold labeling and electron microscopy. SC1 showed a broad expression in a variety of tissues.     

Enhancement of mycobactericidal activity of glutaraldehyde with α,β-unsaturated and aromatic aldehydes

Summary Several ,-unsaturated and aromatic aldehydes were evaluated for antimicrobial activity usingMycobacterium bovis as the test strain. Activity of most of the compounds was determined in the presence and absence of 2% glutaraldehyde. Several compounds highly active against this organism, e.g. 2-pentenal, benzaldehyde, ando-phthalaldehyde showed rapid kill of >10⁵ CFU ml^–1 in 5 min. Activity of ,-unsaturated compounds substituted in the ₁ position showed increasing activity with increasing chain length. Of the aromatic aldehydes tested, benzaldehyde andp-dimethylamino benzaldehyde showed little activity alone, but when combined with 2% glutaraldehyde showed increased activity. Substituents added to the benzaldehyde ring (nitro, chloro, methyl, and methoxy) all detracted from the synergism, but still showed increased activity over the activity of 2% glutaraldehyde. The same affect was noted with disubstituted benzaldehyde compounds but not with substitutedo-phthaladehyde (2-formylformaldehyde).     

Immunochemical properties of the aminopropeptide of procollagen type III

The precursor-specific aminopropeptide of bovine type III procollagen is a strong immunogen in rabbits, guinea pigs and mice and induces antibodies which do not cross-react with type I procollagen. The antibody response is regulated by immune response genes associated with the major histocompatibility complex. Major antigenic determinants were found in the compact, non-collagenous domain (fragment Col 1) located at the N terminus of the aminopropeptide and were destroyed by reduction of disulfide bonds. Minor antigenic determinants independent of disulfide bonds also exist in fragment Col 1 and could be localized on a distinct tryptic peptide. Fragment Col 1 showed a lower affinity for antibody when compared with the intact aminopropeptide which causes a non-parallel shift in radioimmuno-inhibition profiles. Monovalent antibody fragments showed an average tenfold reduction in affinity constant and failed to distinguish between aminopropeptide and fragment Col 1. This indicates that the stronger binding of bivalent antibody by the triple-stranded aminopropeptide is due to multiple interactions with both antibody binding sites which are lost for a single-stranded antigen (Col 1) or with monovalent antibody fragments.     

Extraction and purification of prostaglandins and thromboxane from biological samples for gas chromatographic analysis

An efficient extraction procedure for the isolation of prostaglandins (PGs) from biological samples for their subsequent quantification by gas chromatography-electron capture detection (GC-ECD) is described. PGs were extracted from lung, kidney, spleen and stomach fundus into ethyl acetate at different pHs. The highest recovery and least extraction of contaminating pigments was obtained at pH 4.5. Pigments and other contaminants are removed by thin-layer chromatography using a solvent system chloroform-isopropyl alcohol-ethanol-formic acid (45:5:0.5:0.3). The isolated PGs were determined by GC-ECD after appropriate derivatization. The overall recovery of PGs using this procedure is 60%.     

Herpes simplex virus type 1 recombination: role of DNA replication and viral a sequences.

During the course of infection, elements of the herpes simplex virus type 1 (HSV-1) genome undergo inversion, a process that is believed to occur through the viral a sequences. To investigate the mechanism of this recombinational event, we have developed an assay that detects the deletion of DNA segments flanked by directly repeated a sequences in plasmids transiently maintained in Vero cells. With this assay, we have observed a high frequency of recombination (approximately 8%) in plasmids that undergo replication in HSV-1-infected cells. We also found a low level of recombination between a sequences in plasmids introduced into uninfected cells and in unreplicated plasmids in HSV-1-infected cells. In replicating plasmids, recombination between a sequences occurs at twice the frequency seen with directly repeated copies of a different sequence of similar size. Recombination between a sequences appears to occur at approximately the same time as replication, suggesting that the processes of replication and recombination are closely linked.     

Self-incompatibility in passion fruit: evidence of two locus genetic control

 The self-incompatibility in yellow passion fruit was previously described as homomorphic sporophytic with monofactorial inheritance. Five progenies were obtained by bud-selfing. The plants of these progenies were selfed, reciprocally crossed within each progeny and crossed with known incompatible phenotypes to identify their phenotypic group. Fruit set was evaluated at the 7th day after pollination. Two progenies consisted of two self-incompatible groups, the other three formed three suck groups. The groups were identified as S₁, S₂, S₃, S₄, S₅ and S₆. The results provide evidence that the self-incompatibility of passion fruit is controlled by two loci, the S-gene and another, whose expression needs to be investigated. Received: 20 June 1998 / Accepted: 13 July 1998     

The importance of the marine ornamental reef fish trade in the wider Caribbean

The marine ornamental fish trade began in the 1930s in Sri Lanka, spread to Hawaii and the Philippines in the 1950s, and expanded to a multi-million dollar industry in the 1970s with fisheries established throughout the tropical Pacific, Indian and Atlantic Oceans. Currently, 45 countries supply global markets an estimated 14-30 million fish annually, with an import value of US$28-44 million. The largest suppliers are Indonesia and the Philippines, followed by Brazil, Maldives, Vietnam, Sri Lanka and Hawaii. In the tropical Western Atlantic, 16 countries have export fisheries, including the U.S. (Florida and Puerto Rico). The U.S. is the world's largest buyer, followed by the European Union and Japan. The global trade consists of over 1400 species of reef fishes, of which only about 25 are captive bred on a commercial scale. Damselfish, anemonefish, and angelfish constitute over 50% of the global volume; butterflyfish, wrasses, blennies, gobies, triggerfish, filcfish, hawkfishes, groupers and basselets account for 31% of the trade, and the remaining 16% is represented by 33 families. The most important fishes from the Caribbean are angelfish (six species), seahorses (two species), royal gramma, jawfish, queen triggerfish, redlip blenny, puddingwife, bluehead wrasse, and blue chromis. The Caribbean currently supplies a small percentage of the global trade in marine ornamental species, but ornamental fisheries in this region represent important emerging industries. It is critical that effective ornamental fishery management plans and regulations are developed and enforced, and fishery-dependent and fishery-independent data are collected and utilized in decision making processes to ensure sustainable ornamental fisheries throughout the region.     

Characterization of proteoglycan-containing perineuronal nets by enzymatic treatments of rat brain sections

Proteoglycans are among the major extracellular matrix components of the central nervous system. In the cerebral cortex and many subcortical regions, chondroitin sulphate proteoglycans, which are related to the aggrecan-versican- neurocan family, have been detected immunocytochemically in perineuronal nets that surround various types of neurons. This indicates that, in the brain, there is a nonhomogeneous but defined distribution of extracellular matrix components. The present study is a further attempt to characterize the perineuronal nets in the cerebral cortex. Sections obtained from fixed and unfixed rat brains were subjected to different enzymatic treatments prior to the visualization of perineuronal nets using N-acetylgal actosamine-binding Wisteria floribunda agglutinin, antibodies against chondroitin sulphate proteoglycans or hyaluronectin, and biotinylated hyaluronectin which detects hyaluronan. In all perineuronal nets the binding of the Wisteria floribunda agglutinin was abolished after the incubation of sections with chondroitinase ABC. The protein components of the proteoglycan complexes became easier to digest after removal of chondroitin sulphate chains or hyaluronan. Since only quantitative, and not qualitative, differences in the labelling properties and the structural appearance of cortical perineuronal nets were observed after the various treatments, it is concluded that, with regard to their proteoglycan composition, these structures have common basic properties