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• W2565793553 abstract "<p><b>Non-ribosomal peptide synthetases (NRPS) are large, modular enzymes that synthesisebiologically active secondary metabolites from amino acid precursors without the need for anucleic acid template. NRPS play an integral role in microbial physiology and also havepotential applications in the synthesis of novel peptide molecules. Both of these aspects areexamined in this thesis.</b></p> <p>Under conditions of iron starvation Pseudomonas syringae synthesises siderophores for activeuptake of iron. The primary siderophore of P. syringae is pyoverdine, a fluorescent moleculethat is assembled from amino acid (aa) precursors by NRPS. Five putative pyoverdine NRPSgenes in P. syringae pv. phaseolicola 1448a (Ps1448a) were identified and characterised insilico and their role in pyoverdine biosynthesis was confirmed by gene knockout. Creation ofpyoverdine null Ps1448a enabled identification of a previously uncharacterised temperatureregulatedsecondary siderophore, achromobactin, which is NRPS independent and has loweraffinity for iron. Pyoverdine and achromobactin null mutants were characterised in regard toiron uptake, virulence and growth in iron-limited conditions. Determination of the substratespecificity for the seven adenylation (A) domains of the Ps1448a pyoverdine sidechain NRPSwas also attempted. Although ultimately unsuccessful, these attempts provided a rigorousassessment of methods for the expression, purification and biochemical characterisation of Adomains.</p> <p>The Ps1448a NRPS were subsequently employed in domain swapping experiments to testcondensation (C) domain specificity for aa substrates during peptide formation in vivo.</p> <p>Experiments in which the terminal C- and/or A-domain of the Pseudomonas aeruginosa(PAO1) pyoverdine NRPS system were replaced with alternative domains from Ps1448a andPAO1 were consistent with previous in vitro observations that C-domains exhibit strongsidechain and stereo-selectivity at the downstream aa position, but only stereo-selectivity atthe upstream aa position.</p> <p>These results prompted investigation into the role of inter-domain communication in NRPSfunction, to test the hypothesis that the thiolation (T) domain enters into specific interactionswith other domains, which might provide an alternative explanation for the diminished activityof recombinant NRPS enzymes. A recently characterised single-module NRPS, bpsA, waschosen as a reporter gene for these experiments based on its ability to generate blue pigment inEscherichia coli. Substitution of the native bpsA T-domain consistently impaired function,consistent with the hypothesis. It was shown that directed evolution could be applied to restorefunction in substituted T-domains. Mutations that restored function were mapped in silico, anda structural model for interaction between the thioester (TE) and T-domain of BpsA wasderived.</p> <p>The utility of bpsA for discovery and characterisation of phosphopantetheinyl transferase(PPTase) enzymes was also investigated. In vivo and in vitro assays for determination ofPPTase activity were developed and a high-throughput screen for discovery of new PPTases inenvironmental DNA libraries was successfully implemented.</p>" @default.
• W2565793553 created "2017-01-06" @default.
• W2565793553 creator A5043783257 @default.
• W2565793553 date "2021-11-15" @default.
• W2565793553 modified "2023-10-13" @default.
• W2565793553 title "Characterisation, Manipulation and Directed Evolution of Non-Ribosomal Peptide Synthetase Enzymes" @default.
• W2565793553 cites W1492085418 @default.
• W2565793553 cites W1497937793 @default.
• W2565793553 cites W1500596263 @default.
• W2565793553 cites W1566716279 @default.
• W2565793553 cites W1570250780 @default.
• W2565793553 cites W1587696955 @default.
• W2565793553 cites W1761706241 @default.
• W2565793553 cites W1763493835 @default.
• W2565793553 cites W1790221236 @default.
• W2565793553 cites W1860527785 @default.
• W2565793553 cites W1910828174 @default.
• W2565793553 cites W1931534490 @default.
• W2565793553 cites W1944333546 @default.
• W2565793553 cites W1964516896 @default.
• W2565793553 cites W1965697531 @default.
• W2565793553 cites W1965811910 @default.
• W2565793553 cites W1966524255 @default.
• W2565793553 cites W1967439285 @default.
• W2565793553 cites W1967596986 @default.
• W2565793553 cites W1968217232 @default.
• W2565793553 cites W1969981848 @default.
• W2565793553 cites W1970386034 @default.
• W2565793553 cites W1970756887 @default.
• W2565793553 cites W1971511760 @default.
• W2565793553 cites W1973223043 @default.
• W2565793553 cites W1973311283 @default.
• W2565793553 cites W1974087808 @default.
• W2565793553 cites W1974172219 @default.
• W2565793553 cites W1979557728 @default.
• W2565793553 cites W1979700983 @default.
• W2565793553 cites W1983857548 @default.
• W2565793553 cites W1985863178 @default.
• W2565793553 cites W1986451689 @default.
• W2565793553 cites W1987052754 @default.
• W2565793553 cites W1988521954 @default.
• W2565793553 cites W1990812439 @default.
• W2565793553 cites W1991760145 @default.
• W2565793553 cites W1992956214 @default.
• W2565793553 cites W1993403449 @default.
• W2565793553 cites W1994506742 @default.
• W2565793553 cites W1995195892 @default.
• W2565793553 cites W1995816575 @default.
• W2565793553 cites W1998591058 @default.
• W2565793553 cites W2001937806 @default.
• W2565793553 cites W2002110958 @default.
• W2565793553 cites W2002407169 @default.
• W2565793553 cites W2003006345 @default.
• W2565793553 cites W2003090737 @default.
• W2565793553 cites W2003621313 @default.
• W2565793553 cites W2004244262 @default.
• W2565793553 cites W2006894709 @default.
• W2565793553 cites W2007176538 @default.
• W2565793553 cites W2007343995 @default.
• W2565793553 cites W2008733674 @default.
• W2565793553 cites W2009969961 @default.
• W2565793553 cites W2011241109 @default.
• W2565793553 cites W2011700260 @default.
• W2565793553 cites W2012871310 @default.
• W2565793553 cites W2013612636 @default.
• W2565793553 cites W2013740990 @default.
• W2565793553 cites W2013964846 @default.
• W2565793553 cites W2016761967 @default.
• W2565793553 cites W2018179366 @default.
• W2565793553 cites W2018849951 @default.
• W2565793553 cites W2018936231 @default.
• W2565793553 cites W2018990299 @default.
• W2565793553 cites W2020247473 @default.
• W2565793553 cites W2020486543 @default.
• W2565793553 cites W2023144098 @default.
• W2565793553 cites W2023517469 @default.
• W2565793553 cites W2024599746 @default.
• W2565793553 cites W2025421221 @default.
• W2565793553 cites W2025889664 @default.
• W2565793553 cites W2026741022 @default.
• W2565793553 cites W2026856098 @default.
• W2565793553 cites W2027277404 @default.
• W2565793553 cites W2028207395 @default.
• W2565793553 cites W2028908252 @default.
• W2565793553 cites W2032699674 @default.
• W2565793553 cites W2033047693 @default.
• W2565793553 cites W2033540449 @default.
• W2565793553 cites W2034379310 @default.
• W2565793553 cites W2036080658 @default.
• W2565793553 cites W2039622697 @default.
• W2565793553 cites W2045777307 @default.
• W2565793553 cites W2047261739 @default.
• W2565793553 cites W204753584 @default.
• W2565793553 cites W2047695364 @default.
• W2565793553 cites W2047745952 @default.
• W2565793553 cites W2049553531 @default.
• W2565793553 cites W2049696081 @default.
• W2565793553 cites W2052023645 @default.
• W2565793553 cites W2053489555 @default.
• W2565793553 cites W2055057185 @default.

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