R. D. Fitzgerald's F. L. S. „Australian Orchids“

Ohne Zusammenfassung     

A Review of: “Biological Recognition and Assembly,D. S. Eisenberg,J. A. Lake and C. F. Fox,Eds. Alan R. Liss,New York, 1980; hardbound, 355 pages, $52.00”

Two MMP-7-ase isoenzymes were purified 100-fold from rat muscle extract to apparent homogeneity, with an overall yield of 10%, using homogenization, ultracentrifugation, high-performance aqueous size-exclusion and high-performance anion exchange chromatography methods. When using a TSK G-2000SW column, the separation resulted in a 6-fold purification and 30% recovery of isoenzymes B and C. This concentrated enzyme extract was then passed through a TSK-DEAE-2SW column, using salt gradient at pH 7.5, with an additional 25-fold purification and 90% recovery of the isoenzymes. Two symmetrical enzyme peaks, representing isoenzymes B and C, were detected when performing purity tests of the active enzymes on the anion exchanger and reversed-phase HFLC columns. The procedures involved are extraction, ultracentri-fugation, chromatographies and enzyme assays and require less than five hours.     

Differentiation of F1 hybrids P. nigra J. F. Arnold × P. sylvestris L., P. nigra J. F. Arnold × P. densiflora Siebold et Zucc., P. nigra J. F. Arnold × P. thunbergiana Franco and their parental species by needle volatile composition

The volatile composition of needles from three F₁ hard pine hybrids produced by the controlled hybridization and their parental species were researched with gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS) in order to explore the utility of terpenes in hybrid identification (their differentiation from the parental species) as well as confirmation of hybridity. The analysed hybrids were: 1. Pinus nigra J. F. Arnold × Pinus sylvestris L. (= nisy), 2. P. nigra × Pinus densiflora Siebold et Zucc. (= nide) and 3. P. nigra × Pinus thunbergiana Franco (= nith). A total of 55 compounds were identified. All identified compounds were terpenes, except trans-2-hexenal.Three analysed F₁ hybrids showed the same qualitative pattern of the needle volatile composition as their parental species. However, there were quantitative differences in several major terpenes. The volatile composition of the needles from the hybrids nisy were equally similar to both parents, the hybrids nide were more similar to the female parent (P. nigra), whereas the hybrids nith were more similar to the male parent (P. thunbergiana). According to the content of germacrene D, as the specific component of P. nigra (female parent of the three analysed F₁ hybrids), all hybrids were intermediary in relation to the parental species. The content of Δ-3-carene (the specific component of P. sylvestris) in the hybrids nisy was also intermediary. The hybrids nide had a higher content of thunbergol (specific component of P. densiflora) than the other analysed hybrids. In view of the content of β-pinene, the specific component of P. thunbergiana, the hybrids nith were intermediary to the parental species and that content was considerably higher than in the other analysed hybrids. The intermediary quality of F₁ hybrids for these specific components in relation to the parental species confirms their hybrid character.The needle volatile composition analysis as well as the previous morphometric analysis confirm the hybrid character of three F₁ hybrids, whose female parent is P. nigra, and male parents are P. sylvestris, P. densiflora, i.e. P. thunbergiana.     

Laboratoire de Chimie Bactérienne C.N.R.S., Marsielle, France.

Summary Mutants of E. coli, completely devoid of nitrite reductase activity with glucose or formate as donor were studied. Biochemical analysis indicates that they are simultaneously affected in nitrate reductase, nitrite reductase, fumarate reductase and hydrogenase activities as well as in cytochrome c₅₅₂ biosynthesis. The use of an antiserum specific for nitrate reductase shows that the nitrate reductase protein is probably missing. A single mutation is responsible for this phenotype: the gene affected, nir R, is located close to tyr R i.e. at 29 min on the chromosomal map.Abbreviations BV Benzyl-Viologen - NTG N-methyl-N-nitro-N-nitrosoguanidine - NR nitrate reductase - NIR nitrite reductase - FR fumarate reductase - HYD hydrogenase - CYT c₅₅₂ cytochrome c₅₅₂