Browsing by Author "Lin, SM"

Now showing 1 - 3 of 3

Expression, characterization, and purification of recombinant porcine lactoferrin in Pichia pastoris
(2002-06-01)
Wang, SH
;
Yang, TS
;
Lin, SM
;
Tsai, MS
;
Wu, SC
Recombinant porcine lactoferrin (rPLF) was synthesized in Pichia pastoris using a constitutive promoter from the glyceraldehyde-3-phosphate dehydrogenase gene. Strains expressing rPLF with its own signal sequence or with that from the yeast alpha-mating factor (alpha-MF) were able to produce and secrete rPLF, but levels were consistently higher using alpha-MF constructs. In contrast, P. pastoris strains that expressed rPLF without a signal sequence produced the protein in an insoluble intracellular form. Increasing the initial pH of shake-flask culture medium from 6.0 to 7.0 or adding ferric ions to the medium (to 100 muM) resulted irk significant improvements in expression of rPLF from P. pastoris. Expression levels (approximately 12 mg/L) were much higher than those observed from Saccharomyces cerevisiae strains (1-2 mg/L). P pastoris-secreted rPLF was isolated and purified via a one-step simple procedure using a heparin column. The molecular size (78 kDa), isoelectric point (8.8-9.0), N-terminal amino acid sequence, and iron-binding capability of rPLF were each similar to that of native milk PLF. (C) 2002 Elsevier Science (USA).
Molecular techniques to identify freshwater eels: RFLP analyses of PCR-amplified DNA fragments and allele-specific PCR from mitochondrial DNA
(2002-10-01)
Lin, YS
;
Poh, YP
;
Lin, SM
;
Tzeng, CS
;
生物科技學系
Because of morphological ambiguity, traditional classification of freshwater eel elvers (of the genus Anguilla) has always been difficult and unreliable. This study analyzes 2 mitochondrial genes viz., cytochrome b and 12S ribosomal RNA (rRNA) genes from previous studies, to establish molecular standards for eel identification. Prediction of restriction fragment length polymorphism (RFLP) indicated that a combination of 3 enzyme results for cytochrome b revealed good resolution power. We also selected 39 specific nucleotide sites of the 2 genes at which the site is unique for individual species: thus these can potentially be used for identification by polymerase chain reaction (PCR). To verify the accuracy of our predictions, we examined 58 specimens from 4 species by DpnII and HaeIII digestions and by PCR amplification using species-specific primers. Consistent with the putative mutation rates, more than 95% and 99% of the specimens could be successfully identified by the RFLP and PCR methods, respectively. The molecular techniques developed here can be helpful in eel aquaculture and ecological studies.
The CACTUS object server: Design and implementation issues
(1998)
Meng, IH
;
Yang, WP
;
Lin, SM
;
Chen, MA
;
Chen, SK
CACTUS is a compact and reliable object storage system based an peer-to-peer architecture with distributed transaction processing capability. The kernel is implemented with the multi-thread mechanisms to provide a high performance multi-transaction environment. All sites, installed with CACTUS, of the networked workstations are on an equal footing. The system can handle local and remote transactions including accessing remote objects or processing remote accesses. In this paper. we give an architectural overview of CACTUS and discuss some implementation issues. It mentions the special contributions such as transient large objects, the coarser lack granularity and its associated protocol. A cost model is developed to demonstrate that the new scheme yields performances which are superior in most common cases and inferior under certain situations.