CDNA cloning and expression of autoantigen B0-E2

AIM: To express BO-E2 recombinant fusion protein in Escherichia coli for use in early diagnosis of primary biliary cirrhosis (PBC). METHODS: CDNA encoding BCOADC-E2 and OGDC-E2 were obtained by reverse transcription pdymerase chain reaction (RT-PCR), confirmed by DNA sequencing, subcloned non-directionally into the bacterial expression plasmid pET28a(+), and then transformed into E. coli BL21(DE3) to express the recombinant fusion protein, which was identified by SDS-PAGE and western blotting. RESULTS: Results of nucleotide sequencing and restriction analysis showed that the recombinant plasmid successfully constructed three species. Three types of fusion protein were expressed by isopropyl-Beta-d-thiogalactopyranoside (IPTG) induction. The recombinant fusion protein exhibited the antigenic-ity of AMA-M2 by western blotting. CONCLUSION: BO-E2 recombinant fusion protein can be used for in vitro diagnosis of PBC.link_to_subscribed_fulltex

A measurement of D meson production in Z0 hadronic decays

A study of the fragmentation properties of charm and bottom quarks into D mesons is presented. From 263 700 Z0 hadronic decays collected in 1991 with the DELPHI detector at the LEP collider, D0, D+ and D*+ are reconstructed in the modes K-π+, K-π+K+ and D0π+ followed by D0→K-π+, respectively. The fractional decay widths {Mathematical expression} are determined, and first results are presented for the production of D mesons from {Mathematical expression} and {Mathematical expression} events separately. The average energy fraction of D*± in charm quark fragmentation is found to be 〈XE(D*)〉c=0.487± 0.015 (stat)±0.005 (sys.). Assuming that the fraction of Ds and charm-baryons produced at LEP is similar to that around 10 GeV, the Z0 partial width into charm quark pairs is determined to be Γc/Γh=0.187±0.031 (stat)±0.023 (sys). The probability for a b quark to fragment into {Mathematical expression} or b-baryons is inferred to be 0.268±0.094 (stat)±0.100 (sys) from the measured probability that it fragments into a {Mathematical expression} or B-. © 1993 Springer-Verlag