Read by QxMD icon Read

Heme iron

Victor Yin, Gary Stephen Shaw, Lars Konermann
In addition to serving as respiratory electron shuttle, ferri-cytochrome c (cyt c) acts as a peroxidase, i.e., it catalyzes the oxidation of organic substrates by H2O2. This peroxidase function plays a key role during apoptosis. Typical peroxidases have a five-coordinate heme with a vacant distal coordination site that permits the iron center to interact with H2O2. In contrast, native cyt c is six-coordinate, as the distal coordination site is occupied by Met80. It thus seems counterintuitive that native cyt c would exhibit peroxidase activity...
October 19, 2017: Journal of the American Chemical Society
Moon-Suhn Ryu, Kari A Duck, Caroline C Philpott
Developing red blood cells exhibit multiple, redundant systems for regulating and coordinating the uptake of iron, the synthesis of heme, and the formation of hemoglobin during terminal differentiation. We recently described the roles of poly rC-binding protein (PCBP1) and nuclear coactivator 4 (NCOA4) in mediating the flux of iron through ferritin in developing erythroid cells, with PCBP1, an iron chaperone, delivering iron to ferritin and NCOA4, an autophagic cargo receptor, directing ferritin to the lysosome for degradation and iron release...
September 28, 2017: Blood Cells, Molecules & Diseases
Lucia Hadariová, Matej Vesteg, Vladimír Hampl, Juraj Krajčovič
Chloroplasts are generally known as eukaryotic organelles whose main function is photosynthesis. They perform other functions, however, such as synthesizing isoprenoids, fatty acids, heme, iron sulphur clusters and other essential compounds. In non-photosynthetic lineages that possess plastids, the chloroplast genomes have been reduced and most (or all) photosynthetic genes have been lost. Consequently, non-photosynthetic plastids have also been reduced structurally. Some of these non-photosynthetic or "cryptic" plastids were overlooked or unrecognized for decades...
October 12, 2017: Current Genetics
Eileen S Marks, Mathilde L Bonnemaison, Susan K Brusnahan, Wenting Zhang, Wei Fan, Jered C Garrison, Erika I Boesen
Proteins involved in iron homeostasis have been identified as biomarkers for lupus nephritis, a serious complication of systemic lupus erythematosus (SLE). We tested the hypothesis that renal iron accumulation occurs and contributes to renal injury in SLE. Renal non-heme iron levels were increased in the (New Zealand Black x New Zealand White) F1 (NZB/W) mouse model of lupus nephritis compared with healthy New Zealand White (NZW) mice in an age- and strain-dependent manner. Biodistribution studies revealed increased transferrin-bound iron accumulation in the kidneys of albuminuric NZB/W mice, but no difference in the accumulation of non-transferrin bound iron or ferritin...
October 9, 2017: Scientific Reports
Kimberley L Painter, Alex Hall, Kam Pou Ha, Andrew M Edwards
Small colony variants (SCVs) of Staphylococcus aureus typically lack a functional electron transport chain and cannot produce virulence factors such as leukocidins, hemolysins or the anti-oxidant staphyloxanthin. Despite this, SCVs are associated with persistent infections of the bloodstream, bones and prosthetic devices. The survival of SCVs in the host has been ascribed to intracellular residency, biofilm formation and resistance to antibiotics. However, the ability of SCVs to resist host defences is largely uncharacterised...
October 9, 2017: Infection and Immunity
Hanjun Cheng, Yufeng Liu, Yihui Hu, Yubin Ding, Shichao Lin, Wen Cao, Qian Wang, Jiangjiexing Wu, Faheem Muhammad, Xiaozhi Zhao, Dan Zhao, Zhe Li, Hang Xing, Hui Wei
Metal-organic framework (MOF) nanosheets are a class of two-dimensional (2D) porous and crystalline materials that hold promise for catalysis and biodetection. Although 2D MOF nanosheets have been utilized for in vitro assays, ways of engineering them into diagnostic tools for live animals are much less explored. In this work, a series of MOF nanosheets are successfully engineered into a highly sensitive and selective diagnostic platform for in vivo monitoring of heparin (Hep) activity. The iron-porphyrin derivative is selected as ligand to synthesize a series of archetypical MOF nanosheets with intrinsic heme-like catalytic sites, mimicking pe-roxidase...
October 10, 2017: Analytical Chemistry
Regina A Baglia, Jan Paulo T Zaragoza, David P Goldberg
Heme proteins utilize the heme cofactor, an iron porphyrin, to perform a diverse range of reactions including dioxygen binding and transport, electron transfer, and oxidation/oxygenations. These reactions share several key metalloporphyrin intermediates, typically derived from dioxygen and its congeners such as hydrogen peroxide. These species are composed of metal-dioxygen, metal-superoxo, metal-peroxo, and metal-oxo adducts. A wide variety of synthetic metalloporphyrinoid complexes have been synthesized to generate and stabilize these intermediates...
October 9, 2017: Chemical Reviews
Sylvie E Kandel, Lyrialle W Han, Qingcheng Mao, Jed N Lampe
The metabolism of testosterone to 6β-hydroxytestosterone is a commonly used assay to evaluate human CYP3A enzyme activities. However, previous reports have indicated that CYP3A7 also produces 2α-hydroxytestosterone, and that a 2α-hydroxytestosterone:6β-hydroxytestosterone ratio may be a unique biomarker of the isozyme's activity. Until now, the full metabolite and kinetic profile for testosterone hydroxylation by CYP3A7 has not been fully examined. To this end, we performed a complete kinetic analysis of the 6β-hydroxytestosterone, 2α-hydroxytestosterone and 2β-hydroxytestosterone metabolites for recombinant SupersomeTM CYP3A4, 3A5, and 3A7 enzymes and monitored metabolism in fetal and adult human liver microsomes for comparison...
October 6, 2017: Drug Metabolism and Disposition: the Biological Fate of Chemicals
Yongchao Zhu, Ting An, Ying Liu, Zilu Zhang, Qiubo Yang
The principal etiologic agent in periodontal disease, Porphyromonas gingivalis, generates cysteine proteases that bind heme with domains such as hemagglutinin-2 (HA2). High-affinity HA2-hemin binding supplies the porphyrin and ferric iron needed for growth and virulence. The DHYAVMISK peptide, recently identified at the hemin-binding site of HA2 inhibits hemin binding. We now evaluate the protective effect of vaccination with DGFPGDHYAVMISK (termed DK) against P. gingivalis using a rat infection model. Rats immunized with DK generated anti-peptide serum IgGs and salivary sIgAs (as measured by ELISA)...
October 6, 2017: Molecular Oral Microbiology
Marco Constante, Gabriela Fragoso, Annie Calvé, Macha Samba-Mondonga, Manuela M Santos
Dietary heme can be used by colonic bacteria equipped with heme-uptake systems as a growth factor and thereby impact on the microbial community structure. The impact of heme on the gut microbiota composition may be particularly pertinent in chronic inflammation such as in inflammatory bowel disease (IBD), where a strong association with gut dysbiosis has been consistently reported. In this study we investigated the influence of dietary heme on the gut microbiota and inferred metagenomic composition, and on chemically induced colitis and colitis-associated adenoma development in mice...
2017: Frontiers in Microbiology
Wei Jiang, Jiebing Yang, Xinghuo Wang, Haobo Han, Yan Yang, Jun Tang, Quanshun Li
The aim of this work was to construct a peroxidase mimic for achieving the phenol degradation through Fenton reaction. The enzyme mimic was synthesized through the conjugation of heme with the amino group of 2-amino-1,4-benzene dicarboxylate in UiO-66-NH2 (ZrMOF), namely Heme-ZrMOF. Compared to free heme, the composite Heme-ZrMOF exhibited an obviously enhanced ability for phenol degradation with up to 97.3% of phenol removal after 2h. Meanwhile, it could achieve the easy separation of catalyst from the system and the elimination of iron residues in the process of phenol degradation...
September 27, 2017: Bioresource Technology
Can Zhang, Yongzhao Diao, Weizhen Wang, Jianjun Hao, Muhammad Imran, Hongxia Duan, Xili Liu
The genus Colletotrichum contains a wide variety of important plant pathogens, and Colletotrichum truncatum is one of the most prevalent species of Colletotrichum on chili in China. Demethylation-inhibitor fungicides (DMIs) are currently registered chemical agents for the management of the anthracnose disease caused by Colletotrichum spp. To assess the risk for DMI resistance development, 112 C. truncatum isolates were collected from infected pepper in 13 regions of China. The sensitivity of C. truncatum isolates to five DMI fungicides was determined based on mycelial growth inhibition assay...
2017: Frontiers in Microbiology
Anirban Sen Gupta
In blood, the primary role of RBCs is to transport oxygen via highly regulated mechanisms involving hemoglobin (Hb). Hb is a tetrameric porphyrin protein comprising of two α- and two β-polypeptide chains, each containing an iron-containing heme group capable of binding one oxygen molecule. In military as well as civilian traumatic exsanguinating hemorrhage, rapid loss of RBCs can lead to sub-optimal tissue oxygenation and subsequent morbidity and mortality. In such cases, transfusion of whole blood or RBCs can significantly improve survival...
September 29, 2017: Shock
Antoine Paul, Anthony Drecourt, Floriane Petit, Delphine Dupin Deguine, Christelle Vasnier, Myriam Oufadem, Cécile Masson, Crystel Bonnet, Saber Masmoudi, Isabelle Mosnier, Laurence Mahieu, Didier Bouccara, Josseline Kaplan, Georges Challe, Christelle Domange, Fanny Mochel, Olivier Sterkers, Sylvie Gerber, Patrick Nitschke, Christine Bole-Feysot, Laurence Jonard, Souad Gherbi, Oriane Mercati, Ines Ben Aissa, Stanislas Lyonnet, Agnès Rötig, Agnès Delahodde, Sandrine Marlin
Hearing loss and visual impairment in childhood have mostly genetic origins, some of them being related to sensorial neuronal defects. Here, we report on eight subjects from four independent families affected by auditory neuropathy and optic atrophy. Whole-exome sequencing revealed biallelic mutations in FDXR in affected subjects of each family. FDXR encodes the mitochondrial ferredoxin reductase, the sole human ferredoxin reductase implicated in the biosynthesis of iron-sulfur clusters (ISCs) and in heme formation...
October 5, 2017: American Journal of Human Genetics
Yi Zou, Fang Wang, Yan Wang, Qirui Sun, Yue Hu, Yuezhen Li, Wen Liu, Wenjie Guo, Zhangjian Huang, Yihua Zhang, Qiang Xu, Yisheng Lai
Indoleamine-2,3-dioxygenase-1 (IDO1) is an attractive target for cancer immunotherapy. Herein, a series of novel imidazoleisoindole derivatives were prepared and evaluated for their ability to inhibit IDO1. Among these, derivative 11r was the most active compound with nanomolar potency in the Hela cell-based assay, while showed negligible cellular toxicity. UV-visible spectra study demonstrated that compounds 11p and 11r bound to IDO1 and coordinated with the heme iron. Furthermore, they could significantly promote T cell proliferation, increase IFN-γ production, and reduce the numbers of Foxp3(+) regulatory T cells...
September 18, 2017: European Journal of Medicinal Chemistry
Tue Kjærgaard Nielsen, Morten Rasmussen, Sandrine Demanèche, Sébastien Cecillon, Timothy M Vogel, Lars Hestbjerg Hansen
Bacterial degraders of chlorophenoxy herbicides have been isolated from various ecosystems, including pristine environments. Among these degraders, the sphingomonads constitute a prominent group that displays versatile xenobiotic-degradation capabilities. Four separate sequencing strategies were required to provide the complete sequence of the complex and plastic genome of the canonical chlorophenoxy herbicide-degrading Sphingobium herbicidovorans MH. The genome has an intricate organization of the chlorophenoxy-herbicide catabolic genes sdpA, rdpA, and cadABCD that encode the (R)- and (S)-enantiomer-specific 2,4-dichlorophenoxypropionate dioxygenases and four subunits of a Rieske non-heme iron oxygenase involved in 2-methyl-chlorophenoxyacetic acid degradation, respectively...
September 1, 2017: Genome Biology and Evolution
Ayako Ohbuchi, Mari Kono, Kaihei Kitagawa, Mariko Takenokuchi, Shion Imoto, Katsuyasu Saigo
Formation of neutrophil extracellular traps (NETs) can perpetuate sterile inflammation; thus, it is important to clarify their pathophysiological characteristics. Free heme, derived via hemolysis, is a major contributor to organ damage, and reportedly induces neutrophil activation as well as reactive oxygen species (ROS) production and NET formation. For this study, we examined hemin (Fe(3+) -protoporphyrin IX)-induced NET formation quantitatively in vitro as well as the effects of oxidative stress. NETs formed in vitro from cultured neutrophils were quantitatively detected by using nuclease treatment and Sytox Green, a nucleic acid stain...
September 2017: Biochemistry and Biophysics Reports
Kei Saito, Tohru Fujiwara, Urara Ota, Shunsuke Hatta, Satoshi Ichikawa, Masahiro Kobayashi, Yoko Okitsu, Noriko Fukuhara, Yasushi Onishi, Masahiro Ishizuka, Tohru Tanaka, Hideo Harigae
5-Aminolevulinic acid (ALA) is a precursor for the biosynthesis of porphyrins and heme. Although the oral administration of ALA has been widely applied in clinical settings, the dynamics of its absorption, metabolism, and excretion within enterocytes remain unknown. In this study, after enterocytic differentiation, Caco-2 cells were incubated with 200 µM ALA and/or 100 µM sodium ferrous citrate (SFC) for up to 72 h. Both ALA and the combination of ALA and SFC promoted the synthesis of heme, without affecting the expression of genes involved in intestinal iron transport, such as DMT1 and FPN...
September 2017: Biochemistry and Biophysics Reports
Yasumasa Okazaki, Jonathan Glass
BACKGROUND: Protoporphyrin IX (PP IX), the immediate precursor to heme, combines with ferrous iron to make this product. The effects of exogenous PP IX on iron metabolism remain to be elucidated. Peripheral-type benzodiazepine receptor (PBR) is implicated in the transport of coproporphyrinogen into the mitochondria for conversion to PP IX. We have demonstrated that PBR-Associated Protein 7 (PAP7) bound to the Iron Responsive Element (IRE) isoform of divalent metal transporter 1 (DMT1)...
July 2017: Biochemistry and Biophysics Reports
Yashu Chen, Bijun Xie, Jifang Yang, Jigang Chen, Zhida Sun
Rhodococcus sp. B7740 is a newfound bacterium which was isolated from 25m deep seawater in the arctic. In this paper, Rhodococcus sp. B7740 was firstly discovered to produce abundant natural isoprenoids, including ubiquinone-4(UQ-4), 13 kinds of menaquinones, three rare aromatic carotenoids and more than one common carotenoid. These compounds were identified by UV-Visible, HPLC-APCI-MS/MS and HRMS spectra. Results demonstrated that Rhodococcus sp. B7740 might be a worthy source of natural isoprenoids especially for scarce aromatic carotenoids...
February 1, 2018: Food Chemistry
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"