Marker Gene Monthly Newsletter   

November, 2002

Volume 2, Number 11

© Copyright MGT, Inc., 2007.  Published by Marker Gene Technologies, Inc., The University of Oregon Riverfront Research Park, 1850 Millrace Drive, Eugene, Oregon 97403-1992 USA.  All rights reserved.  For information on the use or copying of the material contained in this document, please contact us at techservice@markergene.com.  Please see below for subscription information and updates.  This newsletter is labeled as an ADVERTISEMENT in accordance with the CAN-SPAM act of 2003, S.877 Public Law: 108-187.

Bacterial Detection using FDG

Fluorescein di-ß-D-Galactopyranoside (FDG, M0250) is a popular substrate for measuring cloned beta-Galactosidase activity in living cells.  It has also found utility in staining and quantifying bacteria, as well as in isolating specific strains of bacteria by fluorescence activated cell-sorting (FACS) analysis.  Interestingly, FDG was found to be about 70 times more sensitive in bacterial  assays than GFP.  For more information about FDG staining of bacteria, see the references below:

• ß-Galactosidase Activity in Single Differentiating Bacterial Cells." F. Russo-Marie, Roederer, M. Sager, B., Herzenberg, L., Proc. Natl. Acad. Sci. USA 90:8194 (1993).
• Nelis, H.; Van Poucke, S. Enzymatic detection of coliforms and Escherichia coli within 4 hours." Water, Air, and Soil Pollution (2000), 123(1-4): 43-52.
• Dreier, Jurg; Breitmaier, Eva B.; Gocke, Elmar; Apfel, Christian M.; Page, Malcolm G. P. Direct influence of S9 liver homogenate on fluorescence signals: impact on practical applications in a bacterial genotoxicity assay." Mutation Research (2002), 513(1-2): 169-182.
• Rowland B ; Purkayastha A ; Monserrat C ; Casart Y ; Takiff H ; McDonough KA (1999) “Fluorescence-based detection of lacZ reporter gene expression in intact and viable bacteria including Mycobacterium species” FEMS Microbiol. Lett. 179(2): 317-25
  

Whole body Luciferase detection in vivo.

Dr. Christopher Contag’s group at Stanford Medical School, along with collaborators at Xenogen Corp. have recently demonstrated the ability to measure light emission from transfected firefly luciferase activity inside living tissues and in vivo by injecting live animals with D-luciferin (M0237).  The ability to measure tumor growth and tumor burden in vivo as well as the possibility to streamline development of many types of therapies, including DNA-based gene therapies and gene vaccines, are exciting.  For more information about whole body luciferase gene analysis, see the references below:

• Christopher H. Contag, Stanley D. Spilman, Pamela R. Contag, Masafumi Oshiro, Brian Eames, Phyllis Dennery, David K. Stevenson, David A. Benaron Visualizing Gene Expression in Living Mammals Using a Bioluminescent Reporter Photochemistry and Photobiology (1997) 66(4): 523-531.
• Pamela R. Contag, I. Nick Olomu, David K. Stevenson and Christopher H. Contag^, Bioluminescent Indicators in Living Mammals Nature Medicine, New Technology Section (1998) 4(2):245-247.

Protein traffic using “caged-GFP”

The movement of proteins inside the cell is an important area of study for understanding their function and interactions with intracellular organelles.  Dr. Jennifer Lipppincott-Schwartz’s lab at NIH’s Cell Biology and Metabolism Branch (NICHD) is studying the trafficking kinetics of proteins traversing the secretory and endocytic pathways and how they are affected by different pharmacological and physiological conditions using some newly developed caged-GFP protein tools.  A new GFP, called PA-GFP (for photo-activatable green fluorescent protein) has been modified at position 203 with a histidine substitution.  This PA-GFP can be activated by a short pulse of light at 413nm and used to follow the distribution of PA-GFP fusion proteins inside the cell in a temporal fashion.  For more information about these cell monitoring techniques, see the references below:

• Hirschberg, K., Miller, C.M, Presley, J.F., Ellenberg, J., Zaal, K., Cole, N.B., Siggia, E., Phair, and Lippincott-Schwartz, J. (1998) Kinetic and morphological analysis of secretory protein traffic in living cells. J. Cell Biol. 143: 1485-1503.
•   Patterson, G.H., Lippincott-Schwartz, J., (2002) A Photoactivatable GFP for Selective Photolabeling of Proteins and Cells. Science 297(5588): 1873-1876.

Human Antibody Production in Plants.

Transgenic plants have been engineered by researchers from the Scripps Research Institute and Epicyte Pharmaceuticals (San Diego, CA) to produce recombinant human monoclonal antibodies.  These plant-based systems can provide significant cost advantages over traditional mammalian cell culture systems. In addition, the unwanted effects of immune-sensitive glycosylation patterns are reduced from expression in plant systems.  Among the antibodies currently under production are those for HSV, HIV, pneumonia (respiratory syncytial virus) and intestinal infection (clostridium difficile). For more information about these plant expression systems, see the references below:

• Zeitlin L, Olmsted S, et al. (1998). "A humanized monoclonal antibody produced in transgenic plants for immunoprotection of the vagina against genital herpes" Nature Biotechnology16:1361-1364:
• Ma JK-C, Lehner T, Stabila P, Fux C, Hiatt AC (1994). "Assembly of monoclonal antibodies with IgG1 and IgA heavy chain domains in transgenic tobacco plants" Euro. Jr. Immunol. 24: 131-138.
• Ma, JK-C, Hiatt AC, Hein MB, Vine ND, Wang F, Stabila P, van Dolleweerd C, Mostov K, Lehner T (1995). "Generation and assembly of secretory antibodies in plants" Science 268: 716-719.
  
  

Lipase Activity measured in Live Cells.

Triacylglycerides are metabolized inside living cells by lipases [EC 3.1.1.3]. In normal serum the concentration of lipase is low. In acute pancreatitis and in pancreatic carcinoma a rise in serum lipase activity occurs, with a mean increase being about 50 times that of normal values. A rise in the serum lipase content is also found in acute and chronic renal diseases.  Sensitive measurement of lipase activity in live cells can be accomplished using the fluorescent substrate 1,2-Dioleoyl-3-(pyren-1-yl)decanoyl-rac Glycerol (M0258).  Upon enzymatic cleavage, the fluorescent fatty acid, pyrenedecanoic acid (M0274) is released, which accumulates in cellular membranes.  Upon eximer formation, the fluorescence of this product shifts to longer wavelength, and can be distinguished from that of the substrate, because it forms eximers inside the membrane (EM: 470nm @ EX: 390nm).  This assay is quantitative and can be used with mammalian or bacterial cell lines.  For more information about this assay see the references below:  NOTE: Marker Gene also sells a convenient Fluorescent Lipase Assay Kit (M0612) with all of the reagents and a detailed protocol for measuring lipase activity in living cells.

• Dousset, N., Negre, A., Salvayre, R., Rogalle, P., Dang, Q.Q., Douste-Blazy, L. (1988). Use of a fluorescent radiolabeled triacylglycerol as a substrate for lipoprotein lipase and hepatic triglyceride lipase. Lipids 23: 605-608.
• Main, L.A., Okumura-Noji, K., Ohnishi, T., Yokoyama, S., (1998) Cholesteryl ester transfer protein reaction between plasma lipoproteins. J. Biochem. (Tokyo) 124: 237-243.
  
  

New Catalog Will Be Available Soon.

The 2003-2004 edition of the Marker Gene catalog is heading to the printers.  Many new products and kits, additional literature references, data and protocols will be included, as well as new information about our old products.  Be sure to add your name to our mailing list.  Please visit our Web site and fill out our Customer Information Form, or e-mail us at techservice@markergene.com and we will have a copy sent out to you.
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Compare Our Quality. 

Marker Gene strives to offer our customers products of the highest quality and at the best possible prices.  Our years of experience allow us to provide timely products for less cost to you.  See our latest Price Comparison Chart that compares our prices with those from several alternate sources, to see if you can save money by switching to Marker Gene (http://www.markergene.com/crossref.htm).  Or visit our website at www.markergene.com and click on the link “COMPARE”.  We think you will appreciate our efforts to keep costs low and maintain excellent quality of our products for your research.  For more information about any of our products, simply telephone us toll free at 1-888-218-4062 or contact us by e-mail at techservice@markergene.com.  We will be happy to send you more about our products and their specifications.

CONTRACT  RESEARCH@markergene.com

Marker Gene Technologies, Inc. has the expertise to perform contract research with you on your project. We have worked with many biotechnology and pharmaceutical companies on successful, proprietary and patented projects.

Contract Research and Development Capabilities in the following areas:

• Established in 1993 at the University of Oregon Riverfront Research Park.
• Screening Assay Development for HTS and uHTS
• Chemical and Cellular Assays – High-Content Screening.
• DNA/RNA (genomics) and protein (proteomics) labeling and assay development.
• Pharmaceutical Intermediates - design, synthesis, and in vitro testing in mammalian cell culture.
• Specializing in Carbohydrate, Lipid, Peptide, and Nucleic Acid Chemistries.
• Fully equipped laboratories (Biochemistry, Chemical Synthesis, Tissue Culture, Analytical).
• Confidentiality, help in patent preparation and filings.

Contact us by telephone at (888) 218-4062 or (541) 342-3760 or FAX us at (541) 342-1960 or you can write to us at  Contract Research, Marker Gene Technologies, Inc., 1850 Millrace Drive, Eugene, Oregon 97403-1992 or contact us by e-mail at: techservice@markergene.com

Marker Gene Accepts Major Credit Cards.

Place your orders now, using Master Card or Visa and save time and money!  Our Customer Assistance Staff can now accept either Master Card or Visa Credit Card orders, securely by telephone (toll-free) at 1-888-218-4062 (Domestic orders only).   We will continue to accept Institutional Purchase Orders for our products, online or by FAX at 1-541-342-1960.  International customers should contact us by e-mail, post or telephone for more information about International Distributors and ordering.  For information on pricing for individual products, or for a quote on bulk quantities of our products or kits, please contact our technical assistance staff at techservice@markergene.com.   We will be happy to assist you. 

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