Photoreversible stretching of a BAPTA chelator marshalling Ca²⁺-binding in aqueous media

• Aurélien Ducrot,
• Arnaud Tron,
• Robin Bofinger,
• Ingrid Sanz Beguer,
• Jean-Luc Pozzo and
• Nathan D. McClenaghan

Beilstein J. Org. Chem. 2019, 15, 2801–2811, doi:10.3762/bjoc.15.273

• μM, respectively). Reversible photoliberation/uptake leading to a variation of free calcium concentration in solution was detected using a fluorescent Ca2+ chemosensor. Keywords: azobenzene; BAPTA; calcium binding; photorelease; photoswitch; Introduction In terms of synthetic calcium binding

• Å for the trans-form to 5.96 Å for the cis-form, which, taken in conjunction with the lengthened N–Ca2+ bond lengths tends to suggest a less tight calcium binding in the photogenerated cis-form as compared to the trans-form, consistent with photo-promoted guest release. Exclusively E-isomers are

• (Figure S3, Supporting Information File 1). On repeating this cycle, slow decomposition was observed, estimated at 14% after 3 cycles. Calcium binding by hosts 1E and 1Z was investigated by spectrophotometry, specifically monitoring aromatic ring chromophores which give rise to absorption bands observed

What contributes to an effective mannose recognition domain?

• Christoph P. Sager,
• Deniz Eriş,
• Martin Smieško,
• Rachel Hevey and
• Beat Ernst

Beilstein J. Org. Chem. 2017, 13, 2584–2595, doi:10.3762/bjoc.13.255

• for the formation of a homodimer of A (Figure 8B) [40]. It is believed that this dimer enables transport of the lectin from the Golgi apparatus to cell membranes [73]. Due to a dislocated glutamate in the side chain of the homodimer (Figure 8B), the affinity for calcium binding and therefore also

• /day [81]. Calcium-dependent lectins require a non-acidic environment, such as found in blood, since at lower pH the glutamate and/or aspartate side chains essential for calcium binding can become partially protonated. Instead, FimHLD forms an extensive hydrogen-bond network in a buried, rigid binding