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We used 2D-PAGE to isolate a light-induced protein (AL-A) that is expressed abundantly in light-growth alfalfa sprouts. The seven amino acids of the N-terminal region of the protein were identified, and we searched for the protein in GenBank using the BLAST program. The results of the homology analysis showed that the amino acid sequence of the isolated protein is most similar to one from a pea plastocyanin. To identify the protein, we amplified and sequenced the DNA fragment encoding AL-A from genomic alfalfa DNA. We found that the AL-A gene was highly homologous (90%) to the sequences from the pea plastocyanin via multiple alignments, and the deduced protein precursor was predicted to be chloroplast-specific via the ChloroP computer program. The protein was named alfalfa-plastocyanin (AL-P). It was characterized as being a light-inducible protein, and RT-PCR analysis showed that AL-P mRNA transcription only occurred in the leaves of the alfalfa plant and the alfalfa seedlings growth in lighted conditions. PCR was also used to amplify the DNA fragment encoding the AL-P promoter (AL-Pp) from genomic alfalfa DNA. PlantCARE analysis of the promoter sequence indicated that both a typical TATA box and a CAAT box were located in the promoter sequence, and some of the cis-elements that are responsible for light responsiveness were also identified within this promoter region. The AL-P gene promoter fused to the β-glucuronidase (GUS) reporter gene has been examined for expression in transgenic alfalfa seedlings. Our findings have a potential application in plant genetic engineering; the AL-Pp may be used to drive the expression of heterologous genes in transgenic alfalfa plants.

Sesquiterpenes such as curcumol ( 1 ) and curdione ( 2 ) are the major ingredients of Rhizoma curcumae . Compounds ( 1 ) and ( 2 ) are isomers of one another and play important roles in Chinese Traditional Medicine. Microbial transformations of naturally occurring curcumol and curdione by Cunninghamella elegans AS 3.2028 were studied. In this research, stereoselective epoxidation at the double bond of curcumol led to 10 S ,14-epoxycurcumol ( 3 ) as the major metabolite, with no detectable 10 R ,14-epoxycurcumol ( 4 ). Epoxidation also occurred at the double bond of curdione, generating both (1 S ,10 S )- and (1 R ,10 R )-1,10-epoxycurdione ( 5 ) and ( 6 ). The diastereomeric excess ( de ) of the S diastereomer was 27%. The selectivity of the biotransformation is discussed.

Clocortolone pivalate is a synthetic corticosteroid that can be used to cure corticosteroid-responsive dermatoses. Three previously unknown impurities detected by HPLC were isolated by semi-preparative LC. Based on the NMR and MS spectral data, these were identified as (6R,9R,16R)-9-chloro-6β-fluoro-11β,21-dihydroxy-16α-methylpregna-1,4-diene-3,20-dione-21-pivalate (Impurity I), (9R,16R)-9-chloro-4-fluoro-11β,21-dihydroxy-16α-methylpregna-1,4-diene-3,20-dione-21-pivalate (Impurity II) and (9R,16R)-9-chloro-6α-fluoro-11β,21-dihydroxy-16α-methylpregna-1,4-diene-3,20-dione-11,21-dipivalate (Impurity III). The possible mechanism of the formation of the impurities is discussed.

The gene targeting combined somatic cell nuclear transfer is very useful in agriculture and medicine. Epigenetic modification of DNA by methylation is significant in regulating gene expression during mammalian development. During gene targeting, epigenetic status of donor cell nuclei may be changed in a series of processes, including homologous recombination, cell selection and cloning. We examined DNA methylation of six genes ( β-actin , VEGF , oct4 , TERT , H19 and Igf2 ) and a repetitive sequence art 2 in blg +/− cell line from β-lactoglobulin (BLG) gene targeted fetus and the cells used for BLG gene targeting serve as control. The results demonstrated that the widespread changes of DNA methylation were found in blg +/− cell line. But the degree of variation was different. DNA methylation of VEGF in blg +/− was noticeably decreased. These observations suggest that DNA methylation variations may impact gene expression and finally induce abnormalities and lethality in later developmental stages.