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Updated: Jun 20, 2026

Quantification of Bacterial Histidine Kinase Autophosphorylation Using a Nitrocellulose Binding Assay
Published on: January 11, 2017
The pH sensitivity of histidine-containing lytic peptides
Zhigang Tu1, Albert Young, Christopher Murphy
1Department of Chemistry, Chemical Biology, and Biomedical Engineering, Stevens Institute of Technology, Hoboken, New Jersey 07030, USA.
None:
Many bioactive peptides are featured by their unique amino acid compositions such as argine/lysine-rich peptides. However, histidine-rich bioactive peptides are hardly found. In this study, histidine-containing peptides were constructed by selectively replacing the corresponded lysine residues in a lytic peptide LL-1 with histidines. Interestingly, all resulting peptides demonstrated pH-dependent activities. The cell lysis activities of these peptides could be increased up to four times as the solution pHs dropped from pH = 7.4 to pH = 5.5. The pH sensitivity of a histidine-containing peptide was determined by histidine substitution numbers. Peptide derivatives with more histidines were associated with increased pH sensitivity. Results showed that not the secondary structures but pH-affected cell affinity changes were responsible for the pH-dependent activities of histidine-containing peptides. The histidine substitution approach demonstrated here may present a general strategy to construct bioactive peptides with desired pH sensitivity for various applications.
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