Entrance channels to coproheme in coproporphyrin ferrochelatase probed by exogenous imidazole binding.

Iron insertion into porphyrins is an essential step in heme biosynthesis. In the coproporphyrin-dependent pathway, specific to monoderm bacteria, this reaction is catalyzed by the monomeric enzyme coproporphyrin ferrochelatase. In addition to the mechanistic details of the metalation of the porphyrin, the identification of the substrate access channel for ferrous iron to the active site is important to fully understand this enzymatic system.

Ultrabroadband two-beam coherent anti-Stokes Raman scattering and spontaneous Raman spectroscopy of organic fluids: A comparative study.

Spontaneous Raman spectroscopy is a well-established diagnostic tool, allowing for the identification of all Raman active species with a single measurement. Yet, it may suffer from low-signal intensity and fluorescent background. In contrast, coherent anti-Stokes Raman scattering (CARS) offers laser-like signals, but the traditional approach lacks the multiplex capability of spontaneous Raman spectroscopy.

Proximal ligand tunes active site structure and reactivity in bacterial L. monocytogenes coproheme ferrochelatase.

Ferrochelatases catalyze the insertion of ferrous iron into the porphyrin during the heme b biosynthesis pathway, which is fundamental for both prokaryotes and eukaryotes. Interestingly, in the active site of ferrochelatases, the proximal ligand coordinating the porphyrin iron of the product is not conserved, and its catalytic role is still unclear. Here we compare the L.

Revisiting catalytic His and Glu residues in coproporphyrin ferrochelatase - unexpected activities of active site variants.

The identification of the coproporphyrin-dependent heme biosynthetic pathway, which is used almost exclusively by monoderm bacteria in 2015 by Dailey et al. triggered studies aimed at investigating the enzymes involved in this pathway that were originally assigned to the protoporphyrin-dependent heme biosynthetic pathway. Here, we revisit the active site of coproporphyrin ferrochelatase by a biophysical and biochemical investigation using the physiological substrate coproporphyrin III, which in contrast to the previously used substrate protoporphyrin IX has four propionate substituents and no vinyl groups.

The Molecular Evolution, Structure, and Function of Coproporphyrinogen Oxidase and Protoporphyrinogen Oxidase in Prokaryotes.

Coproporphyrinogen oxidase (CgoX) and protoporphyrinogen oxidase (PgoX) catalyze the oxidation of the flexible cyclic tetrapyrrole of porphyrinogen compounds into fully conjugated, planar macrocyclic porphyrin compounds during heme biosynthesis. These enzymes are activated via different pathways. CgoX oxidizes coproporphyrinogen III to coproporphyrin III in the coproporphyrin-dependent pathway, whereas PgoX oxidizes protoporphyrinogen IX to protoporphyrin IX in the penultimate step of the protoporphyrin-dependent pathway.

Physical Therapist Interventions to Reduce Headache Intensity, Frequency, and Duration in Patients With Cervicogenic Headache: A Systematic Review and Network Meta-Analysis.

Objective: The aim of this study was to assess the efficacy of physical therapist interventions on the intensity, frequency, and duration of headaches, as well as on the quality of life of patients with cervicogenic headache.

Methods: The following databases were searched up to October 2022: Physiotherapy Evidence Database, Web of Science, Pubmed, and Cochrane Library. Randomized controlled trials assessing the effect of physical therapist interventions on adults with cervicogenic headache were included.

Iron insertion into coproporphyrin III-ferrochelatase complex: Evidence for an intermediate distorted catalytic species.

Understanding the reaction mechanism of enzymes at the molecular level is generally a difficult task, since many parameters affect the turnover. Often, due to high reactivity and formation of transient species or intermediates, detailed information on enzymatic catalysis is obtained by means of model substrates. Whenever possible, it is essential to confirm a reaction mechanism based on substrate analogues or model systems by using the physiological substrates.

Structural aspects of enzymes involved in prokaryotic Gram-positive heme biosynthesis.

The coproporphyrin dependent heme biosynthesis pathway is almost exclusively utilized by Gram-positive bacteria. This fact makes it a worthwhile topic for basic research, since a fundamental understanding of a metabolic pathway is necessary to translate the focus towards medical biotechnology, which is very relevant in this specific case, considering the need for new antibiotic targets to counteract the pathogenicity of Gram-positive superbugs. Over the years a lot of structural data on the set of enzymes acting in Gram-positive heme biosynthesis has accumulated in the Protein Database (www.

Metal phosphine aldehyde complexes and their application in Cu-free Sonogashira and Suzuki-Miyaura cross-coupling reactions.

Transition metal coordination chemistry and catalysis are rife with phosphine ligands. One of the rather less studied members of the phosphine ligand family are phosphine aldehydes. We have synthesised 3-(diphenylphosphino)propanal (PCHO) with a slight modification of the known procedure and studied its complexation behaviour with palladium(II) and platinum(II).

Active site architecture of coproporphyrin ferrochelatase with its physiological substrate coproporphyrin III: Propionate interactions and porphyrin core deformation.

Coproporphyrin ferrochelatases (CpfCs) are enzymes catalyzing the penultimate step in the coproporphyrin-dependent (CPD) heme biosynthesis pathway, which is mainly utilized by monoderm bacteria. Ferrochelatases insert ferrous iron into a porphyrin macrocycle and have been studied for many decades, nevertheless many mechanistic questions remain unanswered to date. Especially CpfCs, which are found in the CPD pathway, are currently in the spotlight of research.

Tunable picosecond optical parametric amplifier pumped by 1 ps pulses at 1 µm for coherent anti-Stokes Raman scattering.

We report an optical parametric amplifier (OPA), providing a maximum pulse energy of ∼200 µJ at 700-950 nm and a pulse duration of ∼1 ps. The OPA is driven by a ∼1 ps pulse with ∼2.5 mJ energy at 1 kHz, provided by a commercial thin-disk based laser.

Life in an optical fiber: Monitoring of cell cultures with microcavity in-line Mach-Zehnder interferometer.

Monitoring cell adhesion and growth are crucial for various applications involving drug screening, cytotoxicity, and cytocompatibility studies. However, acquiring accurate information about the growing state and responsiveness to a treatment of a cell system in a real-time and label-free manner is still a challenge. This work presents the first research on direct, real-time, and label-free adherent cell culture monitoring using a microcavity in-line Mach-Zehnder interferometer (μIMZI) fabricated in an optical fiber.

Single-stage procedures for anorectal malformations: A systematic review and meta-analysis.

Background: The purpose of this study is to describe all published studies of single-stage procedures for anorectal malformations and to perform a meta-analysis of studies that compared single-stage to staged procedures.

Methods: Searches were conducted in Pubmed, Medline, Embase and CENTRAL. Meta-analysis was performed in RevMan and expressed as forest plots with odds ratios (OR) and 95% confidence intervals (CI).

Paediatric Anogenital Condylomata Acuminata: An assessment of patient characteristics and the need for surgical intervention.

Background: Anogenital Condylomata Acuminata (AGCA) are caused by Human Papilloma Virus (HPV), which is one of the most common sexually transmitted illnesses in adults. Although commonly seen in the paediatric population, especially in the setting of immunocompromise, literature regarding transmission, viral type and management in this population is scant. The aim of this study was to assess the profile of patients presenting with anogenital warts in light of associated immunocompromise with Human Immunodeficiency Virus (HIV).

[Effectiveness of physiotherapeutic treatment interventions on pain intensity, duration, frequency, and quality of life of patients with migraine : A systematic review].

Background: According to the current guidelines preventive treatment of migraine should consist of a combination of pharmacological and nonpharmacological forms of treatment. Physiotherapeutic modalities could be an option for nonpharmacological migraine management.

Objective: The aim was to assess the efficacy of physiotherapeutic interventions on pain intensity, duration and frequency as well as the quality of life of patients with migraine.

Substrate specificity and complex stability of coproporphyrin ferrochelatase is governed by hydrogen-bonding interactions of the four propionate groups.

Coproporpyhrin III is the substrate of coproporphyrin ferrochelatases (CpfCs). These enzymes catalyse the insertion of ferrous iron into the porphyrin ring. This is the penultimate step within the coproporphyrin-dependent haeme biosynthesis pathway.

A 7-year retrospective review of renal trauma in paediatric patients in Johannesburg.

Background: South African data on paediatric patients with renal trauma that are usually managed conservatively is scarce. This study aimed to review a 7-year experience of paediatric renal trauma and management.

Methods: A retrospective review of all paediatric admissions with renal injury was conducted in the Department of Paediatric Surgery, University of the Witwatersrand, between 1 January 2012 and 31 December 2018.

Applicability of the revised trauma score in paediatric patients admitted to a South African intensive care unit: A retrospective cohort study.

Context: Revised Trauma Score (RTS) is a validated tool in assessing patients in a pre-hospital setting. There are limited data describing its potential use in guiding referral to intensive care.

Aims: Trauma scoring systems require appropriate validation in a local setting before effective application.

Electrochemistry in an optical fiber microcavity - optical monitoring of electrochemical processes in picoliter volumes.

In this work, we demonstrate a novel method for multi-domain analysis of properties of analytes in volumes as small as picoliters, combining electrochemistry and optical measurements. A microcavity in-line Mach-Zehnder interferometer (μIMZI) obtained in a standard single-mode optical fiber using femtosecond laser micromachining was able to accommodate a microelectrode and optically monitor electrochemical processes inside the fiber. The interferometer shows exceptional sensitivity to changes in the optical properties of analytes in the microcavity.

The Burden of Disease and Pathology at a Rapidly Expanding Tertiary Paediatric Surgical Unit in South Africa.

Background: The precise burden of paediatric surgical care in South Africa is unknown. In the absence of epidemiological data, hospital-based study is a first step to gauge the burden and profile of paediatric surgical disease. We aim to describe the profile of pathology, pattern of referrals, and complications of paediatric surgical care at Chris Hani Baragwanath Academic Hospital (CHBAH).

Neonatal surgical outcomes: a prospective observational study at a Tertiary Academic Hospital in Johannesburg, South Africa.

Purpose: The neonatal period is the most vulnerable period for a child. There is a paucity of data on the burden of neonatal surgical disease in our setting. The aim of this study was to describe the frequency with which index neonatal surgical conditions are seen within our setting and to document the 30-day outcome of these patients.

Effectiveness of a 2-Week Strength Training Learning Intervention on Self-selected Weight-Training Intensity.

Glass, SC, Ahmad, S, and Gabler, T. Effectiveness of a 2-week strength training learning intervention on self-selected weight-training intensity. J Strength Cond Res 34(9): 2443-2448, 2020-The purpose of this study was to determine the effectiveness of an imposed (IM) vs.