Rapid Bacterial Recognition over a Wide pH Range by Boronic Acid-Based Ditopic Dendrimer Probes for Gram-Positive Bacteria

• Published in: Molecules (Basel, Switzerland) Switzerland), 2021-12, Vol.27 (1), p.256
• Main Authors: Mikagi, Ayame, Manita, Koichi, Yoyasu, Asuka, Tsuchido, Yuji, Kanzawa, Nobuyuki, Hashimoto, Takeshi, Hayashita, Takashi
• Format: Article
• Language: English
• Subjects: Acids; Antibiotics; Bacteria; bacterial recognition; Boronic Acids - chemistry; dendrimer; Dendrimers - chemistry; dipicolylamine; E coli; Electrostatic properties; Gram-negative bacteria; Gram-positive bacteria; Gram-Positive Bacteria - physiology; Gram-Positive Bacterial Infections - diagnosis; Gram-Positive Bacterial Infections - microbiology; Humans; Hydrogen-Ion Concentration; Hydrophobic and Hydrophilic Interactions; Hydrophobicity; Metal ions; Molecular Diagnostic Techniques; Molecular Probes; phenylboronic acid; Probes; Recognition; S. aureus; Selectivity; Sensitivity and Specificity; Staphylococcus aureus
• ISSN: 1420-3049; 1420-3049
• DOI: 10.3390/molecules27010256

We have developed a convenient and selective method for the detection of Gram-positive bacteria using a ditopic poly(amidoamine) (PAMAM) dendrimer probe. The dendrimer that was modified with dipicolylamine (dpa) and phenylboronic acid groups showed selectivity toward . The ditopic dendrimer system had higher sensitivity and better pH tolerance than the monotopic PAMAM dendrimer probe. We also investigated the mechanisms of various ditopic PAMAM dendrimer probes and found that the selectivity toward Gram-positive bacteria was dependent on a variety of interactions. Supramolecular interactions, such as electrostatic interaction and hydrophobic interaction, per se, did not contribute to the bacterial recognition ability, nor did they improve the selectivity of the ditopic dendrimer system. In contrast, the ditopic PAMAM dendrimer probe that had a phosphate-sensing dpa group and formed a chelate with metal ions showed improved selectivity toward . The results suggested that the targeted ditopic PAMAM dendrimer probe showed selectivity toward Gram-positive bacteria. This study is expected to contribute to the elucidation of the interaction between synthetic molecules and bacterial surface. Moreover, our novel method showed potential for the rapid and species-specific recognition of various bacteria.