http://hdl.handle.net/123456789/1384 2026-04-14T23:26:46Z http://hdl.handle.net/123456789/5156 Folding forms of Escherichia coli DmsD, a twin-arginine leader binding protein Sarfo, Kwabena J.; Winstone, Tara L.; Papish, Andriyka L.; Howell, Jenika M.; Kadir, Hakan; Vogel, Hans J.; Turner, Raymond J. Escherichia coli DmsD interacts with the twin-arginine leader sequence of the catalytic sub-unit (DmsA) of DMSO reductase. DmsD was purified as a mixture of a number of different folding forms including: dimer (A); monomer (B); a minor thiol oxidized form; a heterogeneously folded or multi-conformational monomer form which displayed a ladder of bands on native-PAGE (D); and proteolytically degraded and aggregated forms. Polyacrylamide gel electrophoresis (PAGE), under denaturing and non-denaturing conditions, was used to examine the folding and stability of DmsD. Additionally, the biophysical methods of dynamic light scattering, circular dichroism, fluorescence, and mass spectroscopy were also used. Form D could be converted to form B by treatment with 4M urea, which is the concentration at which form B begins to denature. Forms A/B could be converted to D by incubation at pH 5.0. Forms A/B and D all had twin-arginine leader binding activity. 2004 Elsevier Inc. All rights reserved 7p:, ill. 2004-01-01T00:00:00Z http://hdl.handle.net/123456789/5155 FcCH~P(CH~OH)~: a new, reactive yet air-stable ferrocene-derived phosphine [Fc = (q0C5H5)FeC5H4] Goodwin, Nicholas J.; Henderson, William; Sarfo, J. Kwabena Reaction of FcCH2NMe3+I- with an excess of P(CH2OH)3 gives the air-stable ferrocenylphosphine FcCH~P(CH~OH)~, characterized by an X-ray structure determination activity towards reagents such as MeI, acrylonitrile and mines allows the synthesis of a range of new ferrocene-phosphined erivative 2p:, ill. 1996-01-01T00:00:00Z http://hdl.handle.net/123456789/5154 Enrichment of tiger nut milk with microbial transglutaminase cross-linked protein improves the physico-chemical properties of the fermented system Kizzie-Hayford; Jaros, Doris; Rohm, Harald Milk proteins cross-linked with microbial transglutaminase were investigated for their potential to improve the microbiological and physico-chemical properties of fermented tiger nut milk. Fermented systems with cross-linked proteins did not affect S. thermophilus viable counts but decreased that of L. delbrueckii ssp. bulgaricus compared to the untreated protein systems. Systems with cross-linked proteins showed shorter microbial lag time and a higher pH reduction rates during fermentation. During storage of the fermented product, viable counts of L. delbrueckii ssp. bulgaricus decreased faster than that of S. thermophilus, and systems with cross- linked proteins revealed a lower decrease in L. delbrueckii ssp. bulgaricus cell counts compared to untreated proteins during 15 d. Products from cross-linked sodium caseinate or whey protein showed 16.4 fold and 3.6 fold increase in viscosity, and approx. 30 % and 36 % decrease in syneresis compared to their untreated counterparts, respectively. The addition of proteins to tiger nut milk improved the lightness of the fermented product and minimized lightness decrease during storage, and casein cross-linking further improved lightness. The enrichment of tiger nut milk with cross-linked protein has therefore a large potential for improving the physical characteristics of fermented tiger nut milk 31p:, ill. 2012-01-01T00:00:00Z http://hdl.handle.net/123456789/5153 Empirical rheology and pasting properties of soft-textured durum wheat (Triticum turgidum ssp. durum) and hard-textured common wheat (T. aestivum) Quayson, Enoch T.; Atwell, William; Morris, Craig F.; Marti, Alessandra Puroindoline (PIN1) proteins are the molecular basis for wheat kernel texture classification and affect flour milling performance. This study investigated the effect of PINs on empirical rheology and pasting properties in T. turgidum ssp. durum and T. aestivum. Soft wheat Alpowa), durum wheat (cv. Svevo) and their derivatives in which PINs were deleted (Hard Alpowa) or expressed (cv. Soft Svevo). Presence of PINs affected flour particle size and damaged starch. PINs increased the pasting temperature and breakdown viscosity, while the effect on peak viscosity and setback were not consistent. Presence of PINs was negatively associated with GlutoPeak gluten aggregation energy and farinograph dough stability, suggesting a weakening of the gluten matrix. As regards dough extensibility, the role of PINs was evident only in common wheat: 5DS distal end deletion increased the resistance to extension, without affecting the dough extensibility. This study showed PINs to have different impact on pasting and rheological properties of T. aestivum and T. turgidum ssp. durum flours 28p:, ill. 2012-01-01T00:00:00Z