It has been found that Ser His could cleave bovine serum albumin(BSA), with the most suitable pH around 6.0. The kinds of buffers have different influences on the cleavage activity. The phosphate buffer and BR buffer ...It has been found that Ser His could cleave bovine serum albumin(BSA), with the most suitable pH around 6.0. The kinds of buffers have different influences on the cleavage activity. The phosphate buffer and BR buffer are the most effective. The hydroxyl group of the serine residue is the essential functional group for the cleavage, while the amide bond, imidazole, and carboxyl group of Ser His increase the cleavage activity.展开更多
Linear and supercoiled DNA were cleaved by HPLC purified seryl histidine dipeptide(SH). It was found that the DNA fragments produced by the reaction of SH and DNA could be ligated together by T 4 DNA ligase. This resu...Linear and supercoiled DNA were cleaved by HPLC purified seryl histidine dipeptide(SH). It was found that the DNA fragments produced by the reaction of SH and DNA could be ligated together by T 4 DNA ligase. This result implied that the SH was the first example of the ion free artificial DNA cleavage agent that could split DNA by hydrolysis mechanism.展开更多
In this work, the change of gas-phase proton affinity of alkyl-alanine through the phosphorylation reaction was studied by the electrospray ionization mass spectrometry with kinetic method. It was proved that the phos...In this work, the change of gas-phase proton affinity of alkyl-alanine through the phosphorylation reaction was studied by the electrospray ionization mass spectrometry with kinetic method. It was proved that the phosphorylation could increase the proton affinity of small peptide. A proposal that proton affinity increase might be responsible for the sensitivity improvement of small peptide in mass spectrometry has been provided.展开更多
The effects of the amino, hydroxyl, imidazole and carboxyl groups of Ser His on DNA cleavage reaction were studied. It was found that the amino and hydroxyl groups were essential for the DNA cleavage activity of Ser H...The effects of the amino, hydroxyl, imidazole and carboxyl groups of Ser His on DNA cleavage reaction were studied. It was found that the amino and hydroxyl groups were essential for the DNA cleavage activity of Ser His, and that anyone of them blocked would result into the loss of cleavage activity. The carboxyl group was not the necessary group. The presence of the imidazole group would enhance the cleavage activity. However, the histidyl serine dipeptide, as the formula isomer of Ser His with the inverse peptide sequence, could not cleave DNA at all. Based on the above experimental results, a presumed cleavage mechanism of Ser His on DNA was proposed. [WT5HZ]展开更多
文摘It has been found that Ser His could cleave bovine serum albumin(BSA), with the most suitable pH around 6.0. The kinds of buffers have different influences on the cleavage activity. The phosphate buffer and BR buffer are the most effective. The hydroxyl group of the serine residue is the essential functional group for the cleavage, while the amide bond, imidazole, and carboxyl group of Ser His increase the cleavage activity.
文摘Linear and supercoiled DNA were cleaved by HPLC purified seryl histidine dipeptide(SH). It was found that the DNA fragments produced by the reaction of SH and DNA could be ligated together by T 4 DNA ligase. This result implied that the SH was the first example of the ion free artificial DNA cleavage agent that could split DNA by hydrolysis mechanism.
文摘In this work, the change of gas-phase proton affinity of alkyl-alanine through the phosphorylation reaction was studied by the electrospray ionization mass spectrometry with kinetic method. It was proved that the phosphorylation could increase the proton affinity of small peptide. A proposal that proton affinity increase might be responsible for the sensitivity improvement of small peptide in mass spectrometry has been provided.
文摘The effects of the amino, hydroxyl, imidazole and carboxyl groups of Ser His on DNA cleavage reaction were studied. It was found that the amino and hydroxyl groups were essential for the DNA cleavage activity of Ser His, and that anyone of them blocked would result into the loss of cleavage activity. The carboxyl group was not the necessary group. The presence of the imidazole group would enhance the cleavage activity. However, the histidyl serine dipeptide, as the formula isomer of Ser His with the inverse peptide sequence, could not cleave DNA at all. Based on the above experimental results, a presumed cleavage mechanism of Ser His on DNA was proposed. [WT5HZ]
