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1.
2.
Polypeptide-metal cluster connectivities in Cd(II) GAL4 总被引:3,自引:0,他引:3
Two-dimensional 1H-113Cd correlation NMR spectra have been used to determine the polypeptide/metal cluster connectivities in Cd(II) GAL4. The results show that the protein contains a two metal ion cluster where Cys-11 and Cys-28 are the bridging ligands. 相似文献
3.
Christopher L. Millington Amanda J. Watson Andrew S. Marriott Geoffrey P. Margison Andrew C. Povey David M. Williams 《Nucleosides, nucleotides & nucleic acids》2013,32(4):328-338
O 6-(carboxymethyl)guanine (O 6-CMG) and O 6-(4-oxo-4-(3-pyridyl)butyl)guanine (O 6-pobG) are toxic lesions formed in DNA following exposure to alkylating agents. O 6-CMG results from exposure to nitrosated glycine or nitrosated bile acid conjugates and may be associated with diets rich in red meat. O 6-pobG lesions are derived from alkylating agents found in tobacco smoke. Efficient syntheses of oligodeoxyribonucleotides (ODNs) containing O 6-CMG and O 6-pobG are described that involve nucleophilic displacement by the appropriate alcohol on a common synthetic ODN containing the reactive base 2-amino-6-methylsulfonylpurine. ODNs containing O 6-pobG and O 6-CMG were found to be good substrates for the S. pombe alkyltransferase-like protein Atl1. [Supplemental materials are available for this article. Go to the publisher's online edition of Nucleosides, Nucleotides & Nucleic Acids to view the free supplemental file.] 相似文献
4.
Somatic cell hybrids have been selected between three pairs of established human lymphoid cell lines producing pure lines of proliferating hybrid cells: Raji/Namalwa, Raji/Daudi, and Raji/BJAB. The hybrid cell lines have been characterized with respect to isozyme pattern, volume, and karyotype. 相似文献
5.
Paulo FP Pimenta Alessandra S Orfano Ana C Bahia Ana PM Duarte Claudia M Ríos-Velásquez Fabrício F Melo Felipe AC Pessoa Giselle A Oliveira Keillen MM Campos Luis Martínez Villegas Nilton Barnabé Rodrigues Rafael Nacif-Pimenta Rejane C Sim?es Wuelton M Monteiro Rogerio Amino Yara M Traub-Cseko José BP Lima Maria GV Barbosa Marcus VG Lacerda Wanderli P Tadei Nágila FC Secundino 《Memórias do Instituto Oswaldo Cruz》2015,110(1):23-47
In the Americas, areas with a high risk of malaria transmission are mainly located in
the Amazon Forest, which extends across nine countries. One keystone step to
understanding the Plasmodium life cycle in Anopheles species from the Amazon Region
is to obtain experimentally infected mosquito vectors. Several attempts to colonise
Ano- pheles species have been conducted, but with only short-lived success or no
success at all. In this review, we review the literature on malaria transmission from
the perspective of its Amazon vectors. Currently, it is possible to develop
experimental Plasmodium vivax infection of the colonised and field-captured vectors
in laboratories located close to Amazonian endemic areas. We are also reviewing
studies related to the immune response to P. vivax infection of Anopheles aquasalis,
a coastal mosquito species. Finally, we discuss the importance of the modulation of
Plasmodium infection by the vector microbiota and also consider the anopheline
genomes. The establishment of experimental mosquito infections with Plasmodium
falciparum, Plasmodium yoelii and Plasmodium berghei parasites that could provide
interesting models for studying malaria in the Amazonian scenario is important.
Understanding the molecular mechanisms involved in the development of the parasites
in New World vectors is crucial in order to better determine the interaction process
and vectorial competence. 相似文献
6.
Maria C Anholeti Rodrigo C Duprat Maria R Figueiredo Maria AC Kaplan Marcelo Guerra Santos Marcelo S Gonzalez Norman A Ratcliffe Denise Feder Selma R Paiva Cicero B Mello 《Memórias do Instituto Oswaldo Cruz》2015,110(5):629-635
Studies evaluated the effects of hexanic extracts from the fruits and flowers
ofClusia fluminensis and the main component of the flower
extract, a purified benzophenone (clusianone), against Aedes
aegypti. The treatment of larvae with the crude fruit or flower extracts
from C. fluminensis did not affect the survival ofAe.
aegypti (50 mg/L), however, the flower extracts significantly delayed
development of Ae. aegypti. In contrast, the clusianone (50 mg/L) isolate from the
flower extract, representing 54.85% of this sample composition, showed a highly
significant inhibition of survival, killing 93.3% of the larvae and completely
blocking development of Ae. aegypti. The results showed, for the first time, high
activity of clusianone against Ae. aegypti that both killed and inhibited mosquito
development. Therefore, clusianone has potential for development as a biopesticide
for controlling insect vectors of tropical diseases. Future work will elucidate the
mode of action of clusianone isolated from C. fluminensis. 相似文献
7.
Jane F. Povey Natalia Perez‐Moral Timothy R. Noel Roger Parker Mark J. Howard C. Mark Smales 《Biotechnology progress》2009,25(5):1217-1227
Biopharmaceutical proteins are often formulated and freeze dried in agents that protect them from deleterious reactions that can compromise activity and authenticity. Although such approaches are widely used, a detailed understanding of the molecular mechanisms of protein stabilization in low water content amorphous glasses is lacking. Further, whilst deterioration chemistries are well described in dilute solution, relatively little is known about the extent and mechanisms by which protein integrity is compromised in the glassy state. Here we have investigated the relationship between protein modification and rate thereof, with variation of pH, carbohydrate excipient, temperature and the glass transition temperature using a model protein, lysozyme. Mass spectrometry analysis and peptide mapping confirm that protein modifications do occur in the glassy state in a time‐, temperature‐, and carbohydrate excipient‐dependent manner. There were clear trends between the buffer pH and the primary modification detected (glycation). Most importantly, there were differences in the apparent reactivities of the lysine residues in the glass compared with those previously determined in solution, and therefore, the well‐characterized solution reactivity of this reaction cannot be used to predict likely sites of modification in the glassy state. These findings have implications for (i) the selection and combinations of formulation components, particularly with regard to glycation in the glassy state, and (ii) the design of procedures and methodologies for the improvement of protein stability in the glassy state. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009 相似文献
8.
9.
Hugh A Simmons Marion M Simmons Yvonne I Spencer Melanie J Chaplin Gill Povey Andrew Davis Angel Ortiz-Pelaez Nora Hunter Danny Matthews Anthony E Wrathall 《BMC veterinary research》2009,5(1):1-9
Background
Colic could be accompanied by changes in the morphology and physiology of organs and tissues, such as the intestine. This process might be, at least in part, due to the accumulation of oxidative damage induced by reactive oxygen (ROS) and reactive nitrogen species (RNS), secondary to intestinal ischemia. Glutathione (GSH), being the major intracellular thiol, provides protection against oxidative injury. The aim of this study was to investigate whether ischemia-induced intestinal injury could be related with alterations in GSH metabolism. 相似文献10.
A. C. Povey F. Jury W. M. Dippnall A. E. Smith S. Thomson B. Mackness 《Biomarkers》2013,18(2):188-202
Previously we reported that in sheep dippers exposed to organophosphates the frequency of paraoxonase (PON1) polymorphisms differed between those with or without self-reported ill health. We have now examined whether polymorphisms in other genes involved in xenobiotic metabolism alter disease risk in this population. There were elevated but non-significant risks associated with the CYP2D6 WT genotype (odds ratio (OR) 1.47, 95% CI 0.83–2.60), or a GSTP1*B or *C allele (OR 1.37, 95% CI 0.88–2.01) or being GSTM1*2/GSTT1*2 homozygous (OR 1.61, 95% CI 0.74–3.48). Similar results were generally obtained after the exclusion of subjects to obtain a more homogenous case-referent population: for double null GSTM1 and GSTT1 homozygotes the OR was 2.06 (95% CI 0.85–2.04). In those also likely to have been exposed to diazinon, risks associated with a GSTP1*B or *C allele (OR 1.82, 95% CI 0.92–3.63) or a GSTM1*2/GSTT1*2 homozygous (OR 2.60, 95% CI 0.72–10.42) were elevated but not to a significant extent. Risk associated with PON1 genotype and phenotype varied with CYP2D6 and GSTP1 genotype but not consistently with a priori hypotheses. Further work is necessary to delineate more clearly pathways of organophosphate activation and non-PON1 pathways of detoxification and to confirm whether CYP and GST polymorphisms alter disease risk in populations exposed to organophosphates. 相似文献