|PG1||Culture of Haemophilus paragallinarum|
Chang Lin-Huang, Yu Wan-Chin
Institute of Organic and Polymeric Materials of the National Taipei University of Technology
Infectious coryza, an economically important disease for the poultry industry, is an acute respiratory disease of chickens caused by Haemophilus paragallinarum (HP). This infectious disease occurs worldwide and produces significant economic losses due to an increased number of culls and a marked drop in egg production, affecting particularly multi-age farms. Commercial vaccines for infectious coryza, typically based on killed HP, are widely available around the world. To reduce the cost of vaccine production, we studied the culture conditions for an H. paragallinarum strain isolated in Taiwan.
|PG2||Site specificity of £\-H abstraction reaction among secondary structure motif ¡V An ab-intio Study|
Hsiu-Feng Lua*, Feng-Yin Lib* and S. H. Lina
aThe Institute of Atomic and Molecular Sciences, Academia Sinica, P. O. Box 23-166, Taipei, Taiwan 106, R.O.C.
The initial step of protein oxidation is studied through £\-H abstraction by an OH radical with various secondary structure motifs of proteins and found that there exist preferential £\-Hs in this kind of abstractions. The typical abstraction mechanism involves three steps, forming a pre-reactive complex before abstraction, the abstraction reaction and the H2O detachment from a post-reactive complex to form the product, C£\-center radical. Using the stability of the pre-reactive complex and the reaction barrier, we provide some explanation for this site preference. The feasibility of £\-H abstraction by OH radical depends not only on the types of secondary structure, but also on the reaction condition, such as in aqueous or in gas phase. Moreover, the reactivity of the abstraction also depends on the location of £\-H in the secondary structure motifs. The preferentiall £\-Hs to be abstracted in £]-sheet are those immediate to the amide or carbonyl group, without involving hydrogen bonding. While in reverse turns, those are near the C-terminal of type I and near the N-terminal of type II. In general, the £\-Hs in £\-helix are more difficult to be abstracted than those in £]-sheet and poly-peptide in linear form. It is consistent with the trend of their bond dissociation energies. Our theoretical rate constant of N-Acetyldiglycin-methylamide (Ac(Gly)2NHCH3) in aqueous, 6.75x108 M-1sec-1 is close to the experimental observation of N-Acetyldiglycinamide (Ac(Gly)2NH2), 8.6x108 M-1sec-1.
|PG3||Proteomic analyses of the manganese regulon of Neisseria gonorrhoeae|
Hsing-Ju Wua, Kuan-Tin Pana, He-Hsuan Hsiaoa, Michael P. Jenningsb, Alastair G. McEwanb, Chen-Wen Yaoc and Andrew H.-J. Wanga
a Core Facilities for Proteomics Research, Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan; b School of Molecular and Microbial Sciences & Centre for Metals in Biology, The University of Queensland, Brisbane, Australia; cChinese Herbal Medicine Research Center, Tri-Service General Hospital, Taiwan
Neisseria gonorrhoeae is an important human pathogen which causes gonorrhoea and pelvic
inflammatory disease, both of which are significant global health problems. It is a
facultative aerobe with a high iron requirement and a highly active aerobic respiratory
chain. These factors would suggest that this bacterium would require defense systems to
respond to toxic oxygen species. In previous studies we have shown that the accumulation
of manganese (Mn) and Mn(II) uptake system, MntABC, in N. gonorrhoeae protected against
killing by superoxide anion, and was independent of superoxide dismutase activity.
Also, investigation of a regulatory role for Mn(II) in N. gonorrhoeae has revealed that
a key virulence factor, pilin, is repressed by Mn via a PerR-independent
post-transcriptional mechanism. To provide a more comprehensive view of the regulatory
network and its molecular mechanism, the shotgun proteomic approach,, i.e. one
dimensional (1D) sodium dodecyl sulfate-polyacrylamide gel electrophoresis (1D-SDS-PAGE)
coupled with 1D liquid chromatography (LC) - tandem mass spectrometry (MS/MS) and the
quantitative method, i.e., isotope coded affinity tag (ICAT) were performed.