Reactions of hemoglobin with phenylhydrazine: a review of selected aspects.

It is well known that phenylhydrazine induces hemolytic anemia. This is thought to result from the reaction of phenylhydrazine with hemoglobin. The accompanying oxidation of phenylhydrazine leads to the formation of a number of products, including benzene, nitrogen, hydrogen peroxide, superoxide anion and the phenyl radical. The products formed depend critically on the conditions of the experiment, especially the amount of oxygen present. It is now known that oxyhemoglobin and myoglobin react with phenylhydrazine to yield a derivative of hemoglobin containing N-phenylprotoporphyrin in which the heme group is modified. The recent identification of sigma-phenyliron(III) porphyrins in phenylhydrazine-modified metmyoglobin has aided elucidation of the mechanism of hemoglobin modification. Mechanistic schemes are proposed to account for product formation

Reactions of hemoglobin with phenylhydrazine: a review of selected aspects.

It is well known that phenylhydrazine induces hemolytic anemia. This is thought to result from the reaction of phenylhydrazine with hemoglobin. The accompanying oxidation of phenylhydrazine leads to the formation of a number of products, including benzene, nitrogen, hydrogen peroxide, superoxide anion and the phenyl radical. The products formed depend critically on the conditions of the experiment, especially the amount of oxygen present. It is now known that oxyhemoglobin and myoglobin react with phenylhydrazine to yield a derivative of hemoglobin containing N-phenylprotoporphyrin in which the heme group is modified. The recent identification of sigma-phenyliron(III) porphyrins in phenylhydrazine-modified metmyoglobin has aided elucidation of the mechanism of hemoglobin modification. Mechanistic schemes are proposed to account for product formation

Chemical RNA digestion enables robust RNA-binding site mapping at single amino acid resolution

© 2020, The Author(s), under exclusive licence to Springer Nature America, Inc. RNA-binding sites (RBSs) can be identified by liquid chromatography and tandem mass spectrometry analyses of the protein-RNA conjugates created by crosslinking, but RBS mapping remains highly challenging due to the complexity of the formed RNA adducts. Here, we introduce RBS-ID, a method that uses hydrofluoride to fully cleave RNA into mono-nucleosides, thereby minimizing the search space to drastically enhance coverage and to reach single amino acid resolution. Moreover, the simple mono-nucleoside adducts offer a confident and quantitative measure of direct RNA-protein interaction. Using RBS-ID, we profiled similar to 2,000 human RBSs and probedStreptococcus pyogenesCas9 to discover residues important for genome editing11sci