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121.
122.
Exploitation of Plasmid pMRC01 To Direct Transfer of Mobilizable Plasmids into Commercial Lactococcal Starter Strains 总被引:1,自引:0,他引:1 下载免费PDF全文
Genetic analysis of the 60.2-kb lactococcal plasmid pMRC01 revealed a 19.6-kb region which includes putative genes for conjugal transfer of the plasmid and a sequence resembling an origin of transfer (oriT). This oriT-like sequence was amplified and cloned on a 312-bp segment into pCI372, allowing the resultant plasmid, pRH001, to be mobilized at a frequency of 3.4 × 10−4 transconjugants/donor cell from an MG1363 (recA mutant) host containing pMRC01. All of the resultant chloramphenicol-resistant transconjugants contained both pRH001 and genetic determinants responsible for bacteriocin production and immunity of pMRC01. This result is expected, given that transconjugants lacking the lacticin 3147 immunity determinants (on pMRC01) would be killed by bacteriocin produced by the donor cells. Indeed, incorporation of proteinase K in the mating mixture resulted in the isolation of transformants, of which 47% were bacteriocin deficient. Using such an approach, the oriT-containing fragment was exploited to mobilize pRH001 alone to a number of lactococcal hosts. These results demonstrate that oriT of pMRC01 has the potential to be used in the development of mobilizable food-grade vectors for the genetic enhancement of lactococcal starter strains, some of which may be difficult to transform. 相似文献
123.
Potent, orally active inhibitors of lipoprotein-associated phospholipase A(2): 1-(biphenylmethylamidoalkyl)-pyrimidones. 总被引:4,自引:0,他引:4
Helen F Boyd Stephen C M Fell Deirdre M B Hickey Robert J Ife Colin A Leach Colin H Macphee Kevin J Milliner Ivan L Pinto D Anthony Rawlings Stephen A Smith Ian G Stansfield Steven J Stanway Colin J Theobald Caroline M Whittaker 《Bioorganic & medicinal chemistry letters》2002,12(1):51-55
A series of 1-(biphenylmethylamidoalkyl)-pyrimidones has been designed as nanomolar inhibitors of recombinant lipoprotein-associated phospholipase A(2) with high potency in whole human plasma. 5-(Pyrazolylmethyl) derivative 16 and 5-(methoxypyrimidinylmethyl) derivative 27 demonstrated excellent pharmacodynamic profiles which correlated well with their pharmacokinetic effects. 相似文献
124.
Norman M. Ursula Smith A. Ian Hickey Michael J. 《International journal of peptide research and therapeutics》2001,8(3-5):195-199
Summary The zinc metalloendopeptidases EC 3.4.24.15 (EP 24.15) and EC 3.4.24.16 (EP 24.16) are closely related ubiquitous enzymes,
which have well-defined in vitro activities in generation and degradation of a range of specific peptide targets. Despite
this, little is known regarding their roles in whole animal physiology. One of the peptides degraded by these enzymes in vitro
is bradykinin, a mediator with potent effects on the vasculature at both systemic and local levels. This review summarises
the work that has examined the role of EP 24.15/24.16 in regulation of the vascular effects of bradykinin in vivo. This work
was made possible by the development of a specific stable inhibitor of these enzymes, JA-2. Use of this inhibitor has shown
that EP 24.15/24.16 are capable of regulating responses induced by exogenous bradykinin. This effect was observed at a systemic
level with an increase in the hypotensive effect of intravenous bradykinin. Further work is required to determine whether
these enzymes also regulate bradykinin produced endogenously. 相似文献
125.
A low-frequency response analysis of three Grass model 7 polygraphs was undertaken. Observed error was generally found to fall within the manufacturer's stated range of +5 to -10% of DC signal height over the frequency range of human respiration (0.1-3 Hz), but this was not the case for frequencies greater than 6 Hz under certain circumstances. The magnitude of error was seen to vary directly with frequency and indirectly with pen-deflection amplitude and paper speed. The pen-oscillograph apparatus was the predominant source of low-frequency error, and this is probably due to pen inertia and pen friction on the writing surface. Two schemes to reduce such error are presented. 相似文献
126.
D R Hickey K Jayaraman C T Goodhue J Shah S A Fingar J M Clements Y Hosokawa S Tsunasawa F Sherman 《Gene》1991,105(1):73-81
Genes encoding tuna, pigeon, and horse cytochromes c were constructed with synthetic oligodeoxyribonucleotides having preferred codons and portions of the iso-1-cytochrome c-encoding gene from the yeast Saccharomyces cerevisiae. The genes were ligated into an expression vector, which contains the normal 5'- and 3'-untranslated regions of the yeast iso-1-cytochrome c gene, and were integrated in single copy into the chromosome. Yeast strains were also constructed with multiple integrated copies of the pigeon gene. The heterologous and normal mRNA levels of the single-copy strains were equivalent. Although the N-terminal methionines were completely cleaved in the heterospecific proteins, the levels of trimethylation of Lys72 and acetylation of N-terminal glycines ranged from 39-78% and 10-70%, respectively. Horse cytochrome c was produced at a nearly normal level, whereas the pigeon and tuna cytochromes c were produced at approx. 40% of the normal levels. The levels of the cytochromes c and growth of the mutant yeast strains indicated that the heterospecific cytochromes c had approx. 50% specific activity in vivo. 相似文献
127.
128.
McArley Tristan. J. Hickey Anthony J. R. Wallace Lisa Kunzmann Andreas Herbert Neill. A. 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2019,189(3-4):399-411
Journal of Comparative Physiology B - Decreased oxygen (O2) availability (hypoxia) is common in rock pools and challenges the aerobic metabolism of fishes living in these habitats. In this study,... 相似文献
129.
130.