Aldehyde day

An aldehyde tag is a protein tag with an aldehyde group that is used in biochemistry for protein characterization.

properties

schematic marking on an aldehyde tag

The aldehyde tag is cloned in front of the protein- coding DNA sequence in a vector . By binding to and by reaction with a generating formylglycine enzyme ( English formylglycine-generating enzyme , FGE), a cysteine of the protein tags for the reactive aldehyde ( formylglycine converted).

The aldehyde then reacts selectively with molecular markings e.g. B. with aminoxy or hydrazide groups . Since the optimal acidic pH of the reaction is toxic to the cells , the reaction is carried out at neutral pH values with a reduced reaction rate of about 10 ⁻⁴ to 10 ⁻³ M ⁻¹ s ⁻¹ . Alternatively, it is also possible to generate reactions with pyrazolones, which can take place under physiological conditions. In contrast to methods of bioorthogonal labeling, the aldehyde tag is generated exclusively by biosynthesis without labeled precursor substances, but the reactive carbonyl group is comparatively less specific and tends to undergo side reactions in cells or cell lysates with cellular proteins and other amines with the formation of a Schiff base while the hydrazide or amine oxide containing molecules can react with cellular metabolites having carbonyl groups, e.g. B. in carbohydrate metabolism .

Alternatively, a ketone tag analogous to the aldehyde tag (also with a carbonyl group) can be generated by bioorthogonal labeling .

literature

JA Prescher, CR Bertozzi: Chemical technologies for probing glycans. In: Cell. Volume 126, Number 5, September 2006, pp. 851-854, ISSN 0092-8674 . doi : 10.1016 / j.cell.2006.08.017 . PMID 16959565 .

Individual evidence

↑ IS Carrico, BL Carlson, Carolyn Bertozzi : Introducing genetically encoded aldehyde into protein. In: Nature chemical biology. Volume 3, Number 6, June 2007, pp. 321-322, ISSN 1552-4450 . doi : 10.1038 / nchembio878 . PMID 17450134 .
^ WP Jencks: Studies on the Mechanism of Oxime and Semicarbazone Formation. In: J. Am. Chem. Soc. (1959), Vol. 81, pp. 475-481.
^ RK Lim, Q. Lin: Bioorthogonal chemistry: recent progress and future directions. In: Chemical communications. Volume 46, Number 10, March 2010, pp. 1589-1600, ISSN 1364-548X . doi : 10.1039 / b925931g . PMID 20177591 . PMC 2914230 (free full text).
^ JA Prescher, CR Bertozzi: Chemistry in living systems. In: Nature chemical biology. Volume 1, Number 1, June 2005, pp. 13-21, ISSN 1552-4450 . doi : 10.1038 / nchembio0605-13 . PMID 16407987 .
↑ Z. Zhang, BA Smith, L. Wang, A. Brock, C. Cho, PG Schultz: A new strategy for the site-specific modification of proteins in vivo. In: Biochemistry. Volume 42, Number 22, June 2003, pp. 6735-6746, ISSN 0006-2960 . doi : 10.1021 / bi0300231 . PMID 12779328 .

[1] IS Carrico, BL Carlson, Carolyn Bertozzi : Introducing genetically encoded aldehyde into protein. In: Nature chemical biology. Volume 3, Number 6, June 2007, pp. 321-322, ISSN 1552-4450 . doi : 10.1038 / nchembio878 . PMID 17450134 .

[2] WP Jencks: Studies on the Mechanism of Oxime and Semicarbazone Formation. In: J. Am. Chem. Soc. (1959), Vol. 81, pp. 475-481.

[3] RK Lim, Q. Lin: Bioorthogonal chemistry: recent progress and future directions. In: Chemical communications. Volume 46, Number 10, March 2010, pp. 1589-1600, ISSN 1364-548X . doi : 10.1039 / b925931g . PMID 20177591 . PMC 2914230 (free full text).

[4] JA Prescher, CR Bertozzi: Chemistry in living systems. In: Nature chemical biology. Volume 1, Number 1, June 2005, pp. 13-21, ISSN 1552-4450 . doi : 10.1038 / nchembio0605-13 . PMID 16407987 .

[5] Z. Zhang, BA Smith, L. Wang, A. Brock, C. Cho, PG Schultz: A new strategy for the site-specific modification of proteins in vivo. In: Biochemistry. Volume 42, Number 22, June 2003, pp. 6735-6746, ISSN 0006-2960 . doi : 10.1021 / bi0300231 . PMID 12779328 .