Navigation Links
Enzyme with a sugar antenna
Date:1/30/2009

This release is available in German.

More than half of all human proteins, as well as many important pharmaceutical agents, are glycoproteins, which means that they contain sugar components. In general, natural glycoproteins do not have a homogeneous sugar component. With modern purification techniques, it is practically impossible to isolate sufficient quantities of homogeneous glycoproteins for systematic biomedical studies. Synthesis in the lab is a good alternativebut also a very complex task. As they report in the journal Angewandte Chemie, scientists led by Carlo Unverzagt at the University of Bayreuth (Germany) have now successfully used a new strategy to synthesize ribonuclease C (RNase C), a glycosylated bovine pancreatic enzyme.

Sugar components play an important role in the water solubility, stability, and folding of glycoproteins. In addition, they participate in molecular -recognition processes, such as cell adhesion or the interaction of host cells with pathogens. The same protein with different sugar moieties can thus have different functions. RNase is an enzyme that occurs in various glycosylated forms. Because this enzyme has been intensively investigated before, it makes an interesting model system for research. RNase C contains a complex sugar component in the form of a double-ended "antenna".

The conventional solid-phase synthesis used to build up peptides one amino acid at a time is much too complex for long peptide chains and sometimes doesn't work at all because of side reactions. Unverzagt and his team thus built up RNase C sequentially from several fragments, connecting them by using "native chemical ligation". In this technique, one peptide fragment is attached to the terminal cysteine group (sulfur-containing amino acid) of a second peptide fragment by means of a thioester groupa selective reaction that results in a natural peptide bond.

The researchers used solid-phase synthesis to make the critical peptide fragment that has the sugar antenna. Another fragment was obtained bacterially by means of a method derived from protein splicing. In this process, a protein sequence (intein) is autocatalytically split off from a fusion protein generated in a cell culture. The difficulty: as well as a terminal cysteine group, this protein fragment contains seven additional cysteines. Their sulfurhydrogen groups are extremely reactive and sensitive toward oxidation. In order to protect them, they were "sealed off" as mixed disulfides. These protective groups could be easily removed afterwards.

Thanks to sophisticated techniques, the team was finally able to correctly attach the individual fragments, fold the enzyme into its natural form, and correctly couple the cysteines into disulfide bridges to form a functional RNase C.


'/>"/>

Contact: Carlo Unverzagt
carlo.unverzagt@uni-bayreuth.de
49-921-552-670
Wiley-Blackwell
Source:Eurekalert  

Related medicine news :

1. Tumors use enzyme to recruit regulatory T-cells and suppress immune response
2. Elliott Extremely Dissatisfied With Genzyme Bid for Bioenvision; Believes Offer Significantly Undervalues Company
3. Scientists reveal DNA-enzyme interaction with first ever real time footage
4. UCSD study reveals the regulatory mechanism of key enzyme
5. UCSD study reveals the regulatory mechanism of key enzyme
6. Enzymes second messenger contributes to cell overgrowth
7. Delaware Court Approves Bioenvision, Genzyme Joint Petition
8. Genzyme and Bayer Schering Pharma AG, Germany to Present New Data on Alemtuzumab in Multiple Sclerosis at ECTRIMS
9. Genzyme Statement Regarding Results of FDA Advisory Committee Meeting on the Use of Phosphate Binders in Chronic Kidney Disease
10. Bioenvision Shareholders Approve Acquisition by Genzyme Corporation
11. Role of a key enzyme in reducing heart disease identified
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Enzyme with a sugar antenna
(Date:5/26/2017)... MN (PRWEB) , ... May 26, 2017 , ... A ... U.S. states with the healthiest seniors are located in the Midwest. With the average ... more and more people are concerned with both the quality and affordability of where ...
(Date:5/26/2017)... , ... May 26, 2017 , ... After raising nearly ... Top gadget will continue to be available at a discounted crowdfunding price on ... stress wherever they are, I also wanted to bring a fidget toy to the ...
(Date:5/26/2017)... ... May 26, 2017 , ... Dr. Alex Rabinovich, a highly-skilled oral surgeon specializing ... blog post on insurance options. If a Bay Area patient has to search for ... and money. Visiting an in-network provider for a second opinion can ensure a patient ...
(Date:5/26/2017)... , ... May 26, 2017 , ... “Just What Happened in the Garden of Eden”: ... the Garden of Eden” is the creation of published author, Penelope Colt, mother, trader, horse ... family moved to NYC when she was three. At six, they moved to Dayton, ...
(Date:5/24/2017)... ... May 24, 2017 , ... In modern research, success ... appropriate instruments for research and understanding the basic principles that were designed to ... on innovations in stereo microscopy for brightfield and fluorescence typically used in laboratories ...
Breaking Medicine News(10 mins):
(Date:5/4/2017)... May 4, 2017  DarioHealth Corp. (NASDAQ: DRIO), a ... big data solutions, today announced that it is teaming ... STI Technologies Limited to lower diabetes healthcare costs in ... innoviCares card, which is available throughout all provinces and ... will be eligible for additional savings when shopping for ...
(Date:5/3/2017)... 2017 A Catheterization Laboratory is an ... facility. Commonly referred to as cath lab, this ... imaging technology to give physicians visual access to ... spaces, a team of physicians perform life-saving procedures ... intervention, congenital heart defect closure, stenotic heart valves, ...
(Date:5/3/2017)... Pa. , May 3, 2017  West ... in innovative solutions for injectable drug administration, announced ... Scientific Affairs and Technical Services, and Diane ... workshops and offering presentations focused on West,s expertise ... injectable products, as well as providing commentary on ...
Breaking Medicine Technology: