Tying Up a Loose End: On the Role of the C‐Terminal CCHHRAG Fragment of the Metalloregulator CueR

The transcriptional regulator CueR is activated by the binding of CuI, AgI, or AuI to two cysteinates in a near-linear fashion. The C-terminal CCHHRAG sequence in Escherichia coli CueR present potential additional metal binding ligands and here we explore the effect of deleting this fragment on the binding of AgI to CueR. CD spectroscopic and ESI-MS data indicate that the high AgI-binding affinity of WT-CueR is significantly reduced in Δ7C-CueR.[111 Ag PAC spectroscopy demonstrates that the WT-CueR metal site structure (AgS2) is conserved, but less populated in the truncated variant. Thus, the function of the C-terminal fragment may be to stabilize the two-coordinate metal site for cognate monovalent metal ions. In a broader perspective this is an example of residues beyond the second coordination sphere affecting metal site physicochemical properties while leaving the structure unperturbed

Impact of opioid-free analgesia on pain severity and patient satisfaction after discharge from surgery: multispecialty, prospective cohort study in 25 countries

Background: Balancing opioid stewardship and the need for adequate analgesia following discharge after surgery is challenging. This study aimed to compare the outcomes for patients discharged with opioid versus opioid-free analgesia after common surgical procedures.Methods: This international, multicentre, prospective cohort study collected data from patients undergoing common acute and elective general surgical, urological, gynaecological, and orthopaedic procedures. The primary outcomes were patient-reported time in severe pain measured on a numerical analogue scale from 0 to 100% and patient-reported satisfaction with pain relief during the first week following discharge. Data were collected by in-hospital chart review and patient telephone interview 1 week after discharge.Results: The study recruited 4273 patients from 144 centres in 25 countries; 1311 patients (30.7%) were prescribed opioid analgesia at discharge. Patients reported being in severe pain for 10 (i.q.r. 1-30)% of the first week after discharge and rated satisfaction with analgesia as 90 (i.q.r. 80-100) of 100. After adjustment for confounders, opioid analgesia on discharge was independently associated with increased pain severity (risk ratio 1.52, 95% c.i. 1.31 to 1.76; P < 0.001) and re-presentation to healthcare providers owing to side-effects of medication (OR 2.38, 95% c.i. 1.36 to 4.17; P = 0.004), but not with satisfaction with analgesia (beta coefficient 0.92, 95% c.i. -1.52 to 3.36; P = 0.468) compared with opioid-free analgesia. Although opioid prescribing varied greatly between high-income and low- and middle-income countries, patient-reported outcomes did not.Conclusion: Opioid analgesia prescription on surgical discharge is associated with a higher risk of re-presentation owing to side-effects of medication and increased patient-reported pain, but not with changes in patient-reported satisfaction. Opioid-free discharge analgesia should be adopted routinely

A Study on the Secondary Structure of the Metalloregulatory Protein CueR: Effect of pH, Metal Ions and DNA

The response of CueR towards environmental changes in solution was investigated. CueR is a bacterial metal ion selective transcriptional metalloregulator protein, which controls the concentration of copper ions in the cell. Although several articles have been devoted to the discussion of the structural and functional features of this protein, CueR has not previously been extensively characterized in solution. Here, we studied the efect of change in pH, temperature, and the presence of specifc or non-specifc binding partners on the secondary structure of CueR with circular dichroism (CD) spectroscopy. A rather peculiar reversible pH-dependent secondary structure transformation was observed, elucidated and supplemented with pKa estimation by PROPKA and CpHMD simulations suggesting an important role of His(76) and His(94) in this process. CD experiments revealed that the presence of DNA prevents this structural switch, suggesting that DNA locks CueR in the α-helical-rich form. In contrast to the non-cognate metal ions HgII, CdII and ZnII, the presence of the cognate AgI ion affects the secondary structure of CueR, most probably by stabilizing the metal ion and DNA-binding domains of the protein

A reference compound for ^199mHg perturbed angular correlation of γ-rays spectroscopy

$^{199m}$ Hg is a very useful probe for perturbed angular correlation of $\gamma$ -rays (PAC) spectroscopy. Here we present $^{199m}$ Hg PAC data for a Hg $^{2+}$ containing compound, Hg(Cys)$_{2}$(s), giving one unique nuclear quadrupole interaction (NQI). Four separate sample preparations were carried out, and measured on analogue and digital PAC setups, leading to the following reference data: $\nu$$_{Q}$ = 1.458(7) GHz and $\eta$ = 0.10(6) . The compound may be applied as an easy-to-synthesize reference sample, providing fast control of the effective anisotropy and time calibration of PAC instruments to be used for $^{199m}$ Hg PAC experiments

Tying Up a Loose End:On the Role of the C-Terminal CCHHRAG Fragment of the Metalloregulator CueR

The transcriptional regulator CueR is activated by the binding of Cu(I), Ag(I), or Au(I) to two cysteinates in a near‐linear fashion. The C‐terminal CCHHRAG sequence in Escherichia coli CueR present potential additional metal binding ligands and here we explore the effect of deleting this fragment on the binding of Ag(I) to CueR. CD spectroscopic and ESI‐MS data indicate that the high Ag(I)‐binding affinity of WT‐CueR is significantly reduced in Δ7C‐CueR.([111) Ag PAC spectroscopy demonstrates that the WT‐CueR metal site structure (AgS(2)) is conserved, but less populated in the truncated variant. Thus, the function of the C‐terminal fragment may be to stabilize the two‐coordinate metal site for cognate monovalent metal ions. In a broader perspective this is an example of residues beyond the second coordination sphere affecting metal site physicochemical properties while leaving the structure unperturbed