http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Ayyadurai, Niraikulam,Prabhu, Nadarajan Saravanan,Deepankumar, Kanagavel,Jang, Yoon Jung,Chitrapriya, Nataraj,Song, Eunjung,Lee, Nahum,Kim, Seog K.,Kim, Byung-Gee,Soundrarajan, Nagasundarapandian,Lee, American Chemical Society 2011 Bioconjugate chemistry Vol.22 No.4
<P>We describe the simple bioconjugation strategy in combination of periodate chemistry and unnatural amino acid incorporation. The residue specific incorporation of 3,4-dihydroxy-<SMALL>l</SMALL>-phenylalanine can alter the properties of protein to conjugate into the polymers. The homogeneously modified protein will yield quinone residues that are covalently conjugated to nucleophilic groups of the amino polysaccharide. This novel approach holds great promise for widespread use to prepare protein conjugates and synthetic biology applications.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/bcches/2011/bcches.2011.22.issue-4/bc2000066/production/images/medium/bc-2011-000066_0005.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/bc2000066'>ACS Electronic Supporting Info</A></P>
Niraikulam Ayyadurai,Rameshkumar Neelamegam,Soundrarajan Nagasundarapandian,Selvakumar Edwardraja,Hyung Soon Park,Soo Jae Lee,Tae Hyeon Yoo,Hyungdon Yoon,이선구 한국생물공학회 2009 Biotechnology and Bioprocess Engineering Vol.14 No.3
In this study, we investigated the efficiencies by which the pET and pQE expression systems produce unnatural recombinant proteins by residue-specific incorporation of unnatural amino acids, a method through which it was found that type of gene expression system tremendously influences the production yield of unnatural proteins in Escherichia coli. Green fluorescent protein (GFP) and a single-chain Fv antibody against c-Met were utilized as model recombinant proteins while Lhomopropargylglycine (Hpg), a methionine analogue that incorporates into the methionine residues of a recombinant protein, was used as model unnatural amino acid. The pET system produced an almost negligible amount of Hpg-incorporated unnatural protein compared to the amount of methionine-incorporated natural protein. However, comparable amounts of unnatural and natural protein were produced by the pQE expression system. The amount of unnatural GFP protein produced through pET expression was not increased despite the over-expression of methionyl tRNA synthetase, which can enhance the activation rate of methionyl-tRNA with a methionine analogue. Incorporation of Hpg decreased the productivity of active GFP by approximately 2.5 fold, possibly caused by the inefficient folding of Hpg-incorporated GFP. Conversely, the productivity of functional anti-c-Met sc-Fv was not influenced by incorporation of Hpg. We confirmed through LC-MS and LCMS/ MS that Hpg was incorporated into the methionine residues of the recombinant proteins produced by the pQE expression system In this study, we investigated the efficiencies by which the pET and pQE expression systems produce unnatural recombinant proteins by residue-specific incorporation of unnatural amino acids, a method through which it was found that type of gene expression system tremendously influences the production yield of unnatural proteins in Escherichia coli. Green fluorescent protein (GFP) and a single-chain Fv antibody against c-Met were utilized as model recombinant proteins while Lhomopropargylglycine (Hpg), a methionine analogue that incorporates into the methionine residues of a recombinant protein, was used as model unnatural amino acid. The pET system produced an almost negligible amount of Hpg-incorporated unnatural protein compared to the amount of methionine-incorporated natural protein. However, comparable amounts of unnatural and natural protein were produced by the pQE expression system. The amount of unnatural GFP protein produced through pET expression was not increased despite the over-expression of methionyl tRNA synthetase, which can enhance the activation rate of methionyl-tRNA with a methionine analogue. Incorporation of Hpg decreased the productivity of active GFP by approximately 2.5 fold, possibly caused by the inefficient folding of Hpg-incorporated GFP. Conversely, the productivity of functional anti-c-Met sc-Fv was not influenced by incorporation of Hpg. We confirmed through LC-MS and LCMS/ MS that Hpg was incorporated into the methionine residues of the recombinant proteins produced by the pQE expression system
Ayyadurai, Niraikulam,Deepankumar, Kanagavel,Prabhu, Nadarajan Saravanan,Lee, Sungu,Yun, Hyungdon Royal Society of Chemistry 2011 Chemical communications Vol.47 No.12
<P><B>One stone, two birds:</B> Here, we have developed a simple and efficient method for the incorporation of multiple unnatural amino acids in a single protein. This single protein exhibited two different novel functionalities acquired from the genetically incorporated unnatural amino acids, which is an interesting and not an inherent property of the protein.</P> <P>Graphic Abstract</P><P><B>One stone, two birds:</B> Here, we have developed multiple unnatural amino acids incorporation method in a single protein. This single protein exhibited two different novel functionalities acquired from the genetically incorporated UAA which is not an inherent property of the protein. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c0cc04672h'> </P>
Ayyadurai, Niraikulam,Prabhu, Nadarajan Saravanan,Deepankumar, Kanagavel,Kim, Aran,Lee, Sun-Gu,Yun, Hyungdon Kluwer Academic Publishers 2011 Biotechnology letters. Vol.33 No.11
<P>Introduction of a fluorine moiety into green fluorescent protein offers an interesting novel spectral variant. The calculated binding energy of fluorotyrosine (F-Tyr) (-8.42 kcal/mol) for tyrosyl tRNA synthetase was moderately higher than that of tyrosine (Tyr) (-8.36 kcal/mol). This result directly correlated with the expression level of F-Tyr containing GFP (38 mg/l), which was comparably higher than that of the parent GFP expression level (34 mg/l). Finally, we generated a model structure for GFP to assess possible interaction in the chromophore of the protein structure, which plays an important role in determining the spectral and folding behaviors of the F-Tyr incorporated GFP variant.</P>