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1.
The DNA of fifteen Italian cultivars of durum wheat (Triticum turgidum L. ssp. durum) were analyzed by in fluorescence amplified fragment length polymorphism (fAFLP) in order to obtain the characteristic fingerprintings
of genotypes and assess their genetic relatedness. Among 64 combinations of fluorescence labelled primers, three different
combinations were chosen as producing a total of 6630 AFLP fragments, 2277 (34.3 %) of them being polymorphic. By using this
fAFLP methodology a DNA fingerprinting of each durum wheat cultivar was generated for genotype identification. Analysis of
the genetic relationships show the low variability among durum wheat cultivars. 相似文献
2.
J B Jupiter A K Kour M D Palumbo M J Yaremchuk 《Plastic and reconstructive surgery》1991,88(6):943-51; discussion 952-4
In four complex cases of extremity reconstruction, we have been able to overcome the problems of combined bone and soft-tissue loss and length discrepancy by a combination of free-tissue transfer and the Ilizarov method of slow distraction. It is our observation that gradual distraction of a free tissue is a safe and viable procedure; the free tissue tolerates the pins of the circular external fixator well, and there is an equal degree of distraction and regeneration of the transferred free tissue and the native recipient tissue without evidence of wound dehiscence. Corticotomy through free tissue and in close proximity to vascularized bone is safe, with the subsequent bone regeneration not unlike that of normal bone. Manipulation by slow distraction does not appear to compromise the vasculature of the recipient bed for later microsurgical procedures or endanger the axial flow pattern of the transferred free tissue. 相似文献
3.
François Baneyx Amanda Ayling Terry Palumbo Daniel Thomas George Georgiou 《Applied microbiology and biotechnology》1991,36(1):14-20
Summary The expression of many secreted recombinant proteins in Gram-negative bacteria is limited by degradation in the periplasmic space. We have previously shown that the production of protein A--lactamase, a secreted fusion protein highly sensitive to proteolysis in Escherichia coli, can be increased in mutant strains deficient in up to three cell-envelope-associated proteolytic activities. In this work we investigated the effect of fermentation conditions on suppressing any residual proteolytic activity in various protease-deficient strains. Optimal production of the fusion protein was observed in cells grown under mildly acidic conditions (5.5pH6.0) and at low temperatures. These conditios were shown to specifically decrease the rate of proteolysis. In addition, a further increase in production was observed in cultures supplemented with 0.5 to 0.75 mM zinc chloride. This may relate to the inhibition of a cell envelope protease by Zn2+ ions.
Offsprint requests to: G. Georgiou 相似文献
4.
Cloning and structural characterization of a human non-erythroid band 3-like protein. 总被引:15,自引:3,他引:12 下载免费PDF全文
D R Demuth L C Showe M Ballantine A Palumbo P J Fraser L Cioe G Rovera P J Curtis 《The EMBO journal》1986,5(6):1205-1214
5.
The interactions of Des-Trp1-Nle12-minigastrin I (Nle11-HG-13) and Nle15-little gastrin I (Nle15-HG-17) with calcium ions have been investigated in water and in trifluoroethanol solution using uv and CD absorption techniques. Both hormones strongly interact with Ca2+ in the organic medium. In the case of Nle11-HG-13, the near-uv chiroptical properties (dominated by the transitions of the Trp residue in the C-terminal tetrapeptide sequence) indicate that three metal ions per mole of hormone are involved in the binding process. From the different response of near-uv and far-uv CD properties to the addition of calcium and from the change of the CD spectra in the aromatic absorption region, it is concluded that the biologically important C-terminal sequence is directly involved in the interaction with calcium. Elongation of the peptide chain from Nle11-HG-13 to Nle15-HG-17 (Nle15-little gastrin I) does not provide any additional binding site for calcium ions. The change of the CD properties in the near- and far-uv indicates that three metal ions per mole of hormone are involved in the binding process. The dichroic absorption in the aromatic region indicates that only one of the two Trp residues of the little gastrin analog is sensitive to the presence of calcium. On the assumption that the variation of the CD properties is proportional to the extent of calcium binding, the binding constants K1, K2, and K3 have been estimated roughly. Two similar sets of binding constants have been found, with K1 ≥ 106M?1 and K3 of the order of 105M?1, indicating similar binding sites in the two hormones with high affinity for calcium ions. 相似文献
6.
Growth measurements on surface colonies of bacteria 总被引:4,自引:0,他引:4
7.
8.
Fiorito Serena Collevecchio Chiara Epifano Francesco Genovese Salvatore Palumbo Lucia 《Phytochemistry Reviews》2023,22(1):73-84
Phytochemistry Reviews - Oxyprenylated secondary metabolites of plant, fungal, and microbial origin have emerged as biologically active natural compounds with a great potential for the next future.... 相似文献
9.
10.
Size of Suspended Bacterial Cells and Association of Heterotrophic Activity with Size Fractions of Particles in Estuarine and Coastal Waters 总被引:14,自引:8,他引:6 下载免费PDF全文
The size of bacteria and the size distribution of heterotrophic activity were examined in estuarine, neritic, and coastal waters. The data indicated the small size of suspended marine bacteria and the predominance of free-living cells in numerical abundance and in the incorporation of dissolved amino acids. The average per-cell volume of suspended marine bacteria in all environments was less than 0.1 μm3. Cell volume ranged from 0.072 to 0.096 μm3 at salinities of 0 to 34.3‰ in the Newport River estuary, N.C., and from 0.078 to 0.096 μm3 in diverse areas of the Gulf of Mexico. Thus, the free-living bacteria were too small to be susceptible to predation by copepods. In the Newport River estuary, ca. 93 to 99% of the total number of cells and 75 to 97% of incorporated tritium (from 3H-labeled mixed amino acids) retained by a 0.2-μm-pore-size filter passed through a 3.0-μm-pore-size filter. Although the amino acid turnover rate per cell was higher for the bacteria in the >3.0-μm size fraction than in the <3.0-μm size fraction, the small number of bacteria associated with the >3.0-μm size particles resulted in the low relative contribution of attached bacteria to total heterotrophic activity in the estuary. For coastal and neritic samples, collected off the coast of Georgia and northeast Florida and in the plume of the Mississippi River, 56 to 98% of incorporated label passed through a 3.0-μm-pore-size filter. The greatest activity in the >3.0-μm fraction in the Georgia Bight was at nearshore stations and in the bottom samples. Our data were consistent with the hypothesis that resuspension of bottom material is an important factor in influencing the proportion of heterotrophic activity attributable to particle-associated bacteria. 相似文献