against various organic dyes. The Szostak lab also coined the term aptamer from the Latin, apto ... aptamer selection as a means for application and discovery. In 2001, the process of in vitro selection ... the secondary structural requirements of a cocaine binding aptamer by a thermodynamic and mutation ... aptamer. journal J. Mol. Biol. year 2000 volume 301 pages 117 128 pmid 10926496 ref ref cite journal ..., G. Legge, R. Willson title Biophysical Characterization of DNA Aptamer Interactions with Vascular ... structure of an RNA aptamer bound to thrombin journal RNA year 2008 volume 14 pages 2504 2512 pmid ... of Hemin Binding DNA Aptamer with Peroxidase Activity journal Bulletin of the Chemical Society of Japan ..., a targeted anti VEGF aptamer for ocular vascular disease. journal Nature Reviews Drug Discovery ... R. coauthors M. DeRosa title Retention of function in the DNA homolog of the RNA dopamine aptamer ... 19699181 ref In the case of lysozyme, HIV TAR, VEGF and dopamine the DNA aptamer is the analog of the RNA aptamer, with thymine replacing uracil. The hemin, thrombin, and interferon , DNA and RNA ... H, S parameters of aptamer target interaction. Kinetic capillary electrophoresis is the technology ... developments in aptamer based therapeutics have been rewarded in the form of the first aptamer based ... and clearance from the body by the kidneys, a result of the aptamer s inherently low molecular weight. Unmodified aptamer applications currently focus on treating transient conditions such as blood ... aptamer under development by Schering AG for cancer imaging. Several modifications, such as 2 ..., an FDA approved aptamer are available to scientists with which to increase the serum half life ... resistance of aptamers is to use a Spiegelmer . In addition to the development of aptamer based therapeutics ..., CO have been developing diagnostic techniques for aptamer based plasma protein profiling called aptamer plasma proteomics . This technology will enable future multi biomarker protein measurements ... more details
Infobox rfam Name PreQ1 riboswitch image RF00522.jpg width caption Predicted secondary structure and sequence conservation of PreQ1 Symbol PreQ1 AltSymbols Rfam RF00522 miRBase miRBase family RNA type Cis regulatory element Cis reg riboswitch Tax domain Bacteria GO SO SO 0000035 CAS number EntrezGene HGNCid OMIM PDB RefSeq Chromosome Arm Band LocusSupplementaryData The PreQ1 I riboswitch is a cis acting element identified in bacteria which regulates expression of genes involved in biosynthesis of the nucleoside queuosine from Guanosine triphosphate GTP ref name pmid17384645 cite journal author Roth A, Winkler WC, Regulski EE, Lee BW, Lim J, Jona I, Barrick JE, Ritwik A, Kim JN, Welz R, Iwata Reuyl D, Breaker RR title A riboswitch selective for the queuosine precursor preQ1 contains an unusually small aptamer domain journal Nat Struct Mol Biol volume 14 issue 4 pages 308 317 year 2007 pmid 17384645 doi 10.1038 nsmb1224 ref . This RNA element known as a riboswitch binds preQ sub 1 sub pre queuosine sub 1 sub , an intemediate in the queuosine pathway. Riboswitch function has been characterised in the bacterium Bacillus subtilis , where the riboswitch is located in the leader of the ykvJKLM queCDEF operon which encodes four genes necessary for queuosine production ref name pmid14660578 cite journal author Reader JS, Metzgar D, Schimmel P, de Cr cy Lagard V title Identification of four genes necessary for biosynthesis of the modified nucleoside queuosine journal J. Biol. Chem. volume 279 issue 8 pages 6280 6285 year 2004 pmid 14660578 doi 10.1074 jbc.M310858200 ref . In this organism, PreQ sub 1 sub binding to the riboswitch aptamer is thought to induce premature Transcription genetics transcription termination within the leader to down regulate expression of these genes. The preQ sub 1 sub riboswitch is distinguished by its unusually small aptamer, compared to other riboswitches. Its atomic resolution three dimensional structure was determined. ref cite journal author K ... more details
aptamer s of extremely high binding affinity to a variety of target ligands, including small ..., Feigon J. 1996 . Solution structure of an ATP binding RNA aptamer reveals a novel fold. RNA 2 7 628 40. ref and adenosine ref name Huizenga Huizenga DE, Szostak JW. 1995 . A DNA aptamer that binds adenosine ... binding single stranded DNA aptamers. Tumour Biol 27 6 289 301. ref and a VEGF binding aptamer trade ... References reflist External links http aptamer.freebase.com Aptamer Base Further reading cite ... more details
AptamerBinding.png thumb upright 1.5 Microscale thermophoresis aptamer protein binding assay. The thermophoretic movement of the fluorescently labeled aptamer changes upon binding to the protein File SigmoidalBindingCurveAptamer.png thumb upright 1.5 Sigmoidal binding curve of aptamer in blood serum. The thermophoretic movement of the aptamer decreases normalized fluorescence increases upon binding of the protein. The negativ control aptamer mutant shows no binding of the protein. The sigmoidal ... quantifies Buffer dependence of Aptamer Binding journal Angew. Chem. Int. Ed. volume 49 issue ... more details
Unreferenced stub auto yes date December 2009 Drugbox Verifiedfields changed verifiedrevid 464197562 IUPAC name image Clinical data tradename Macugen Drugs.com drugs.com monograph macugen MedlinePlus a607057 pregnancy US B legal US Rx only routes of administration Intravitreal Pharmacokinetic data bioavailability protein bound metabolism elimination half life 10 days excretion Identifiers ChemSpiderID Ref chemspidercite correct chemspider ChemSpiderID NA CAS number Ref cascite correct ?? CAS number 222716 86 1 ATC prefix S01 ATC suffix LA03 PubChem 24847876 DrugBank Ref drugbankcite correct drugbank DrugBank DB04895 UNII Ref fdacite correct FDA UNII 2H1PA8H1EN ChEMBL Ref ebicite changed EBI ChEMBL 1201704 Chemical data C 294 H 342 F 13 N 107 Na 28 O 188 P 28 molecular weight 50 kilodaltons Pegaptanib sodium injection brand name Macugen is an anti angiogenics anti angiogenic medicine for the treatment of neovascular wet age related macular degeneration AMD . It was discovered by Gilead Sciences and licensed in 2000 to EyeTech Pharmaceuticals, now OSI Pharmaceuticals , for late stage development and marketing in the United States. Outside the U.S.A. Macugen is marketed by Pfizer . Approval was granted by the Food and Drug Administration United States U.S. Food and Drug Administration FDA in December 2004. Pegaptanib is a pegylated anti Vascular endothelial growth factor VEGF aptamer , a single strand of nucleic acid that binds with specificity to a particular target. Pegaptanib specifically binds to VEGF 165, a protein that plays a critical role in angiogenesis the formation of new blood vessels and increased permeability leakage from blood vessels , two of the primary pathological processes responsible for the vision loss associated with neovascular AMD. Pegaptanib is administered in a 0.3 mg dose once every six weeks by intravitreal injection. Ocular vascular disorder agents Category Ophthalmology drugs Category Gilead Sciences Category Pfizer Pharma stub de Pe ... more details
Infobox rfam Name S adenosyl methionine SAM riboswitch, image SAM IV secondary structure.jpg width caption Predicted secondary structure and sequence conservation of SAM IV Symbol SAM IV AltSymbols Rfam RF00634 miRBase miRBase family RNA type Cis regulatory element Cis reg riboswitch Tax domain Bacteria GO SO SO 0005836 CAS number EntrezGene HGNCid OMIM PDB RefSeq Chromosome Arm Band LocusSupplementaryData SAM IV riboswitches are a kind of riboswitch that specifically binds S adenosylmethionine SAM ref cite journal author Weinberg Z, Regulski EE, Hammond MC, et al. title The aptamer core of SAM IV riboswitches mimics the ligand binding site of SAM I riboswitches journal RNA volume 14 issue 5 pages 822 year 2008 pmid 18369181 doi 10.1261 rna.988608 pmc 2327355 ref , a cofactor used in many methylation reactions. Originally identified by bioinformatics ref cite journal author Weinberg Z, Barrick JE, Yao Z, et al. title Identification of 22 candidate structured RNAs in bacteria using the CMfinder comparative genomics pipeline journal Nucleic Acids Res. volume 35 issue 14 pages 4809 19 year 2007 pmid 17621584 doi 10.1093 nar gkm487 pmc 1950547 ref , SAM IV riboswitches are largely confined to the Actinomycetales , an order of Bacteria . Conserved features of SAM IV riboswitch and experiments imply that they probably share a similar SAM binding site to another class of SAM binding riboswitches called SAM riboswitch SAM I riboswitches . However, the scaffolds of these two types of riboswitch appear to be quite distinct. See also SAM riboswitch S box leader SAM I riboswitch SAM II riboswitch SMK box riboswitch SAM III riboswitch SAM V riboswitch References references External links Rfam id RF00634 name SAM IV riboswitch DEFAULTSORT Sam Iv Riboswitch Category Cis regulatory RNA elements Category Riboswitch molecular cell biology stub ... more details
Smart ligands are affinity ligands selected with pre defined equilibrium math K d math , kinetic math k off math , math k on math and thermodynamic H, S parameters of biomolecular interaction. Ligands with desired parameters can be selected from large combinatorial libraries of biopolymers using instrumental separation techniques with well described kinetic behaviour, such as Kinetic capillary electrophoresis KCE , Surface Plasmon Resonance SPR , Microscale Thermophoresis MST ref name Baaske cite journal author Baaske P, Wienken CJ, Reineck P, Duhr S, Braun D title Optical Thermophoresis quantifies Buffer dependence of Aptamer Binding journal Angew. Chem. Int. Ed. volume 49 issue 12 pages 1 5 year 2010 month Feb pmid 20186894 pmc doi 10.1002 anie.200903998 url laysummary http www.physorg.com news186225693.html laysource Phsyorg.com ref ref name Wienken cite journal author Wienken CJ et al. title Protein binding assays in biological liquids using microscale thermophoresis journal Nature Communications year 2010 month Oct volume 1 doi 10.1038 ncomms1093 issue 7 url http www.nature.com ncomms journal v1 n7 full ncomms1093.html bibcode 2010NatCo...1E.100W pages 100 ref and etc. Known examples of smart ligands include DNA smart aptamers however, RNA and peptide smart aptamer s can also be developed. Smart ligands can find a set of unique applications in biomedical research, drug discovery and proteomic studies. For example, a panel of DNA smart aptamers has been recently used to develop affinity analysis of proteins with ultra wide dynamic range of measured concentrations. References Reflist cite journal author Drabovich AP, Berezovski MV, Musheev MU, Krylov SN title Selection of smart small molecule ligands the proof of principle journal Anal. Chem. volume 81 issue 1 pages 490 4 year 2009 month January pmid 19055427 doi 10.1021 ac8023813 cite journal author Drabovich A, Berezovski M, Krylov SN title Selection of smart aptamers by equilibrium capillary electrophoresis ... more details
Infobox Non profit Non profit name Freshman Research Initiative Non profit logo File FRI logo .png Non profit type founded date 2005 founder location The University of Texas Austin origins focus Education Through Research students 600 year revenue key people http cns.utexas.edu deans office curriculum programs ohris Sarah Simmons Director subsid homepage http fri.cns.utexas.edu The Freshman Research Initiative FRI , developed at the University of Texas at Austin , is an innovative model in undergraduate education that offers hundreds of first year students in the University of Texas at Austin College of Natural Sciences College of Natural Sciences the opportunity to advance academically while doing cutting edge, authentic, publishable research in chemistry , biochemistry , nanotechnology , molecular biology , physics , astronomy and computer sciences . The collaborative efforts of http cns.utexas.edu deans office curriculum programs ohris Sarah Simmons , http www.cm.utexas.edu david laude David Laude , http www.cm.utexas.edu ruth shear Ruth Shear , in addition to a group of faculty members at the College of Natural Sciences , led to the launch of http fri.cns.utexas.edu FRI in 2005. The pilot program started with 45 students enrolled in three Research Streams http fri.cns.utexas.edu interactome mapping The Vertebrate Interactome Mapping Stream , which was established by http www.biosci.utexas.edu mgm People Faculty profiles ?id 1807 Scott Stevens , the http aptamer.cns.utexas.edu Aptamer Selection Home.html Aptamer Stream led by http ellingtonlab.org index.html Andy Ellington and https sites.google.com site frinanostream home The Nanomaterials for Chemical Catalysis Stream , which was established by http www.cm.utexas.edu keith stevenson Keith Stevenson , http vandenbout.cm.utexas.edu research Vanden Bout Group David Vanden Bout.html David Vanden Bout and http rcrooks.cm.utexas.edu research Richard Crooks . Currently, about 600 freshmen each year are enrolled in the ... more details
Infobox rfam Name SAM V image SAM V SScon.png width caption Conserved secondary structure of the SAM V riboswitch. Symbol SAM V AltSymbols Rfam RF01826 RNA type Cis regulatory element Cis reg Riboswitch Tax domain Metagenomics Marine metagenome SAM V riboswitch is the fifth known riboswitch to bind S adenosyl methionine SAM . It was first discovered in the marine organism Pelagibacter ubique Candidatus Pelagibacter ubique and can also be found in marine metagenomics metagenomes . ref name Mey09 cite journal author Meyer MM, Ames TD, Smith DP, et al. title Identification of candidate structured RNAs in the marine organism Candidatus Pelagibacter ubique journal BMC Genomics volume 10 issue pages 268 year 2009 pmid 19531245 pmc 2704228 doi 10.1186 1471 2164 10 268 url http www.biomedcentral.com 1471 2164 10 268 accessdate 2010 08 20 ref SAM V features a similar consensus sequence and secondary structure as the binding site of SAM II riboswitch , but bioinformatics scans cluster the two aptamer aptamers independently. These similar binding pockets suggest that the two riboswitches have undergone convergent evolution . ref name Poi09 cite journal author Poiata E, Meyer MM, Ames TD, Breaker RR title A variant riboswitch aptamer class for S adenosylmethionine common in marine bacteria journal RNA volume 15 issue 11 pages 2046 56 year 2009 month November pmid 19776155 pmc 2764483 doi 10.1261 rna.1824209 url http rnajournal.cshlp.org cgi pmidlookup?view long&pmid 19776155 accessdate 2010 08 20 ref SAM binding was confirmed using equilibrium dialysis . The riboswitch has been characterised as a tandem riboswitch it is able to regulate both translation genetics translation and transcription genetics transcription . When SAM is present in high concentration, SAM II will bind its ligand and form a terminator genetics terminator stem to halt transcription. If SAM exists in lower concentrations, SAM V will be transcribed and, if SAM concentration should then increase, it can bind ... more details
Infobox rfam Name Glycine riboswitch image RF00504.jpg width caption Predicted secondary structure and sequence conservation of Glycine Symbol Glycine AltSymbols gcvT Rfam RF00504 miRBase miRBase family RNA type Cis regulatory element Cis reg riboswitch Tax domain Bacteria GO SO SO 0000035 CAS number EntrezGene HGNCid OMIM PDB RefSeq Chromosome Arm Band LocusSupplementaryData The bacterial glycine riboswitch is an Cis regulatory element RNA element that can bind the amino acid glycine . Glycine riboswitch es usually consist of two metabolite binding aptamers domains with similar structures in tandem. The aptamers cooperatively bind glycine to regulate the expression of downstream genes. In Bacillus subtilis , this riboswitch is found upstream of the gcvT operon which controls glycine degradation. It is thought that when glycine is in excess it will bind to both aptamers to activate these genes and facilitate glycine degradation. ref name breaker cite journal last Mandal first M coauthors Lee M, Barrick JE, Weinberg Z, Emilsson GM, Ruzzo WL, Breaker RR year 2004 title A glycine dependent riboswitch that uses cooperative binding to control gene expression journal Science volume 306 pages 275&ndash 279 pmid 15472076 doi 10.1126 science.1100829 issue 5694 ref Examples of the glycine riboswitch exhibit sigmoidal binding curves with Hill coefficient s greater than one, indicating cooperativity positive cooperativity between the two aptamer domains. ref name breaker ref cite journal last Kwon first M coauthors Strobel SA year 2008 title Chemical basis of glycine riboswitch cooperativity journal RNA volume 14 pages 25&ndash 34 pmid 18042658 doi 10.1261 rna.771608 issue 1 pmc 2151043 ref This type of binding is unusual for a riboswitch and is thought to have important physiological consequences. Glycine levels in a bacterial cell must be maintained at a certain baseline level to support protein synthesis . Positive cooperativity would allow genes for glycine degradation to b ... more details
Infobox rfam Name SAM riboswitch alpha proteobacteria image RF00521.jpg width caption Predicted secondary structure and sequence conservation of SAM alpha Symbol SAM alpha AltSymbols Rfam RF00521 miRBase miRBase family RNA type Cis regulatory element Cis reg riboswitch Tax domain Bacteria GO GO 0045814 SO SO 0000035 CAS number EntrezGene HGNCid OMIM PDB RefSeq Chromosome Arm Band LocusSupplementaryData The SAM II riboswitch is a Cis regulatory element RNA element found predominantly in alpha proteobacteria that binds S adenosyl methionine SAM ref name pmid16086852 cite journal author Corbino KA, Barrick JE, Lim J, et al. title Evidence for a second class of S adenosylmethionine riboswitches and other regulatory RNA motifs in alpha proteobacteria journal Genome Biol. volume 6 issue 8 pages R70 year 2005 pmid 16086852 doi 10.1186 gb 2005 6 8 r70 pmc 1273637 ref . Its structure and sequence appear to be unrelated to the SAM riboswitch S box leader SAM riboswitch found in Gram positive bacteria . This SAM riboswitch is located upstream of the metA and metC genes in Agrobacterium tumefaciens , and other methionine and SAM biosynthesis genes in other alpha proteobacteria. Like the other SAM riboswitch, it probably functions to turn off expression of these genes in response to elevated SAM levels. A significant variant of SAM II riboswitches was found in Pelagibacter ubique and related marine ocean marine bacteria and called SAM V riboswitch SAM V . ref cite journal author Poiata E, Meyer MM, Ames TD, Breaker RR title A variant riboswitch aptamer class for S adenosylmethionine common in marine bacteria journal RNA volume 15 issue 11 pages 2046 56 year 2009 month November pmid 19776155 pmc 2764483 doi 10.1261 rna.1824209 url ref Also, like many structured RNAs, SAM II riboswitches can tolerate long loops between their stems. ref name Weinberg2010 cite journal author Weinberg Z, Wang JX, Bogue J, et al. title Comparative genomics reveals 104 candidate structured RNAs from ba ... more details
Infobox rfam Name ykoK leader image RF00380.jpg width caption Predicted secondary structure and sequence conservation of ykoK Symbol ykoK AltSymbols Rfam RF00380 miRBase miRBase family RNA type Cis regulatory element Cis reg Tax domain Bacteria GO SO SO 0000233 CAS number EntrezGene HGNCid OMIM PDB RefSeq Chromosome Arm Band LocusSupplementaryData File Magnesium sensor RNA pdb 2qbz.png thumb 200px left A 3D representation of the Ykok leader. Structure of the M box riboswitch aptamer domain from Bacillus subtilis . ref name pmid17803910 cite journal author Dann CE, Wakeman CA, Sieling CL, Baker SC, Irnov I, Winkler WC title Structure and mechanism of a metal sensing regulatory RNA. journal Cell volume 130 issue 5 pages 878 92 year 2007 pmid 17803910 doi 10.1016 j.cell.2007.06.051 ref The Ykok leader or M box is a Mg sup 2 sup sensing Cis regulatory element RNA structure that controls the Gene expression expression of Magnesium transporter Magnesium ion transport proteins in bacteria. It is a distinct structure to the Magnesium responsive RNA element . The Ykok leader was originally described as a conserved sequence conserved sequence with potential riboswitch function found upstream molecular biology upstream of the B. subtilis ykoK gene and genes with related functions in other bacteria. ref name Barrick cite journal last Barrick first JE coauthors Corbino KA, Winkler WC, Nahvi A, Mandal M, Collins J, Lee M, Roth A, Sudarsan N, Jona I, Wickiser JK, Breaker RR year 2004 title New RNA motifs suggest an expanded scope for riboswitches in bacterial genetic control journal Proc Natl Acad Sci USA volume 101 pages 6421&ndash 6426 pmid 15096624 doi 10.1073 pnas.0308014101 issue 17 pmc 404060 ref Examples of the conserved M box RNA structure occur upstream of each of the three major families of Mg sup 2 sup transporters CorA, MgtE and MgtA MgtB in various bacterial species. ref name pmid17803910 ref The molecular structure of the M box example upstream of the B. subtilis yko ... more details
File PreQ1 II.svg left frame Consensus secondary structure of PreQ sub 1 sub II riboswitches. Layout is similar to that used in previously published depictions. ref name Weinberg2007 ref name meyer Infobox rfam Name preQ1 II pre queuosine riboswitch image preQ1 II secondary structure.jpg width caption Predicted secondary structure and sequence conservation of preQ1 II Symbol preQ1 II AltSymbols COG4708 Rfam RF01054 miRBase miRBase family RNA type Cis regulatory element Cis reg riboswitch Tax domain Bacteria GO SO SO 0005836 CAS number EntrezGene HGNCid OMIM PDB RefSeq Chromosome Arm Band LocusSupplementaryData PreQ1 II riboswitches form a class of riboswitch es that specifically bind pre queosine sub 1 sub PreQ sub 1 sub , a precursor of the modified nucleoside queuosine ref name meyer cite journal author Meyer MM, Roth A, Chervin SM, Garcia GA, Breaker RR title Confirmation of a second natural preQ1 aptamer class in Streptococcaceae bacteria journal RNA volume 14 issue 4 pages 685 year 2008 pmid 18305186 doi 10.1261 rna.937308 pmc 2271366 ref . They are found in certain species of Streptococcus and Lactococcus , and were originally identified as a conserved RNA secondary structure called the COG4708 motif ref name Weinberg2007 cite journal author Weinberg Z, Barrick JE, Yao Z, et al. title Identification of 22 candidate structured RNAs in bacteria using the CMfinder comparative genomics pipeline journal Nucleic Acids Res. volume 35 issue 14 pages 4809 19 year 2007 pmid 17621584 doi 10.1093 nar gkm487 pmc 1950547 ref . All known members of this riboswitch class appear to control members of COG4708 genes. These genes are predicted to encode membrane bound proteins and have been proposed to be a transporter of preQ sub 1 sub , or a related metabolite, based on their association with preQ sub 1 sub binding riboswitches ref name meyer . PreQ1 II riboswitches have no apparent similarities in sequence or structure to preQ1 riboswitch preQ1 I riboswitches , a previously di ... more details
Orphan date August 2011 Infobox rfam Name Mesoplasma florum riboswitch image MFR secondary structure.jpg width caption Predicted secondary structure and sequence conservation of MFR Symbol MFR AltSymbols Rfam RF01510 miRBase miRBase family RNA type Cis regulatory element Cis reg riboswitch Tax domain Bacteria GO GO 0032546 GO 0031554 SO SO 0000035 CAS number EntrezGene HGNCid OMIM PDB RefSeq Chromosome Arm Band LocusSupplementaryData Riboswitches are cis acting regulatory elements located within the 5 untranslated region UTR of mRNA transcripts. These regulatory elements bind small molecules which results in a conformational change within the 5 UTR of the mRNA. The changes in the mRNA secondary structure subsequently result in changes in the expression of the adjacent open reading frame. Bioinformatic studies have identified several riboswitches present in M. florum . ref name pmid17911257 cite journal author Kim JN, Roth A, Breaker RR title Guanine riboswitch variants from Mesoplasma florum selectively recognize 2 deoxyguanosine journal Proc. Natl. Acad. Sci. U.S.A. volume 104 issue 41 pages 16092 7 year 2007 month October pmid 17911257 pmc 1999398 doi 10.1073 pnas.0705884104 url ref These riboswitches have been mapped to regions located upstream of the guaAB operon and resemble purine riboswitch es. The riboswitches identified in M. florum can be classed as novel riboswitches as they deviate in sequence and structure within the loops regions that are required in aptamer binding compared to conventional purine riboswitches. Mutagenesis confirmed that changing nucleotides within the loop regions of this riboswitch altered the specificity for ligand binding. This study showed that the novel riboswitches have a greater diversity in ligands they bind as they were found to bind alternative ligands such as nucleosides . The novel riboswitches were all shown to lie upstream of a putative intrinsic terminator stem and this indicates that these riboswitches control Transcri ... more details
the detection of aptamer binding by comparison of the bound versus unbound motion of the target molecule ... for Quantifying the Buffer Dependence of Aptamer Binding journal Angewandte Chemie International ... more details
, known to bind kink turns in the ribosome, favor SAM aptamer folding by interacting with P2 kink ... aptamer is determined by the formation of a K turn dependant pseudoknot journal Biochemistry ... more details
Wikify date April 2012 Orphan date April 2012 span Image L RNA3D.png thumb 3 D structural model of a Spiegelmer fragment Spiegelmers The word Spiegel is derived from German and means mirror are ribonucleic acid RNA like molecules built from the unnatural L ribonucleotides. They are artificial oligonucleotides and their name is derived from the fact that they are stereochemically mirror images of natural oligonucleotides. Spiegelmers are a form of aptamer s. Due to the use of L nucleotides, they are characterized by high enzymatic stability. Spiegelmers are considered potential drugs and are currently being tested in clinical trials. Features Chemical Properties Image DL Ribose.svg thumb Spiegelmers are the stereochemical mirror images enantiomers of natural oligonucleotides made using L nucleotides. Nucliec acid aptamers, including Spiegelmers, contain adenosine monophosphate AMP , guanosine monophosphate GMP , cytidine monophosphate CMT and uridine monophosphate UMP , a phosphate group, a nucleobase and a Ribose sugar. By replacing the natural D ribose with its enantiomer, L ribose, artificial L nucleotides which are the building blocks of Spiegelmers, can be made. Biological characteristics Like other aptamers, Spiegelmers are able to bind molecules such as peptides, proteins and low molecular weight substances. The affinity of Spiegelmers to their target molecules often lies in the pico to nanomolar range and is thus comparable to antibodies. ref name pmid12070349 cite journal author Wlotzka B, Leva S, Eschgf ller B, et al. title In vivo properties of an anti GnRH Spiegelmer an example of an oligonucleotide based therapeutic substance class journal Proc. Natl. Acad. Sci. U.S.A. volume 99 issue 13 pages 8898 902 year 2002 month June pmid 12070349 pmc 124395 doi 10.1073 pnas.132067399 url ref Spiegelmers themselves have low antigenicity. In contrast to other aptamers,Spiegelmers have high stability in blood serum since they are less susceptible to be cleaved hydrol ... more details
molecule binding RNAs called aptamer s. ref cite journal author Nou X, Kadner RJ title Adenosylcobalamin ... into two parts an aptamer and an expression platform. The aptamer directly binds the small molecule, and the expression platform undergoes structural changes in response to the changes in the aptamer ... cooperative binding , which is accomplished by two adjacent aptamer domains in the same mRNA. Lysine ... previously believed was the domain of protein s or artificially constructed RNAs called aptamer s. The existence ... more details
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