Comparative analysis of xenobiotic metabolising N-acetyltransferases from ten non-human primates as in vitro models of human homologues.

Xenobiotic metabolising N-acetyltransferases (NATs) perform biotransformation of drugs and carcinogens. Human NAT1 is associated with endogenous metabolic pathways of cells and is a candidate drug target for cancer. Human NAT2 is a well-characterised polymorphic xenobiotic metabolising enzyme, modulating susceptibility to drug-induced toxicity.

Drug metabolism and antibiotic resistance in micro-organisms.

This article is part of a themed section on Drug Metabolism and Antibiotic Resistance in Micro-organisms. To view the other articles in this section visit http://onlinelibrary.wiley.

Investigation of the mycobacterial enzyme HsaD as a potential novel target for anti-tubercular agents using a fragment-based drug design approach.

Background And Purpose: With the emergence of extensively drug-resistant tuberculosis, there is a need for new anti-tubercular drugs that work through novel mechanisms of action. The meta cleavage product hydrolase, HsaD, has been demonstrated to be critical for the survival of Mycobacterium tuberculosis in macrophages and is encoded in an operon involved in cholesterol catabolism, which is identical in M. tuberculosis and M.

Recent progress in N-acetyltransferase research: 7th international workshop on N-acetyltransferases (NAT): workshop report.

The 7th International Workshop on N-Acetyltransferases (NAT), held from 18 to 20 June 2016, was hosted by Brunhilde Blömeke and her team at the Trier University (Germany). The workshop addressed important aspects and latest advancements in the fields of NAT enzymes, endogenous functions of NATs, NAT gene nomenclature, genetic polymorphisms, and their associations with diseases as well as their use in diagnosis. Representatives from the leading teams performing research on NATs presented their excellent work, discussed the latest results, and created new ideas in the field of N-acetyltransferase research.

Pathogenic mycobacteria achieve cellular persistence by inhibiting the Niemann-Pick Type C disease cellular pathway.

Background: Tuberculosis remains a major global health concern. The ability to prevent phagosome-lysosome fusion is a key mechanism by which intracellular mycobacteria, including , achieve long-term persistence within host cells. The mechanisms underpinning this key intracellular pro-survival strategy remain incompletely understood.

Identification of novel members of the bacterial azoreductase family in Pseudomonas aeruginosa.

Azoreductases are a family of diverse enzymes found in many pathogenic bacteria as well as distant homologues being present in eukarya. In addition to having azoreductase activity, these enzymes are also suggested to have NAD(P)H quinone oxidoreductase (NQO) activity which leads to a proposed role in plant pathogenesis. Azoreductases have also been suggested to play a role in the mammalian pathogenesis of Pseudomonas aeruginosa.

Characterisation of a putative AraC transcriptional regulator from Mycobacterium smegmatis.

MSMEG_0307 is annotated as a transcriptional regulator belonging to the AraC protein family and is located adjacent to the arylamine N-acetyltransferase (nat) gene in Mycobacterium smegmatis, in a gene cluster, conserved in most environmental mycobacterial species. In order to elucidate the function of the AraC protein from the nat operon in M. smegmatis, two conserved palindromic DNA motifs were identified using bioinformatics and tested for protein binding using electrophoretic mobility shift assays with a recombinant form of the AraC protein.

Differences between murine arylamine N-acetyltransferase type 1 and human arylamine N-acetyltransferase type 2 defined by substrate specificity and inhibitor binding.

Background: The mouse has three arylamine N-acetyltransferase genes, (MOUSE)Nat1, (MOUSE)Nat2 and (MOUSE)Nat3. These are believed to correspond to (HUMAN)NAT1, (HUMAN)NAT2 and NATP in humans. (MOUSE)Nat3 encodes an enzyme with poor activity and human NATP is a pseudogene.

Exploration of piperidinols as potential antitubercular agents.

Novel drugs to treat tuberculosis are required and the identification of potential targets is important. Piperidinols have been identified as potential antimycobacterial agents (MIC < 5 μg/mL), which also inhibit mycobacterial arylamine N-acetyltransferase (NAT), an enzyme essential for mycobacterial survival inside macrophages. The NAT inhibition involves a prodrug-like mechanism in which activation leads to the formation of bioactive phenyl vinyl ketone (PVK).

Identification of NAD(P)H quinone oxidoreductase activity in azoreductases from P. aeruginosa: azoreductases and NAD(P)H quinone oxidoreductases belong to the same FMN-dependent superfamily of enzymes.

Water soluble quinones are a group of cytotoxic anti-bacterial compounds that are secreted by many species of plants, invertebrates, fungi and bacteria. Studies in a number of species have shown the importance of quinones in response to pathogenic bacteria of the genus Pseudomonas. Two electron reduction is an important mechanism of quinone detoxification as it generates the less toxic quinol.

From arylamine N-acetyltransferase to folate-dependent acetyl CoA hydrolase: impact of folic acid on the activity of (HUMAN)NAT1 and its homologue (MOUSE)NAT2.

Acetyl Coenzyme A-dependent N-, O- and N,O-acetylation of aromatic amines and hydrazines by arylamine N-acetyltransferases is well characterised. Here, we describe experiments demonstrating that human arylamine N-acetyltransferase Type 1 and its murine homologue (Type 2) can also catalyse the direct hydrolysis of acetyl Coenzyme A in the presence of folate. This folate-dependent activity is exclusive to these two isoforms; no acetyl Coenzyme A hydrolysis was found when murine arylamine N-acetyltransferase Type 1 or recombinant bacterial arylamine N-acetyltransferases were incubated with folate.

Structure-activity relationships and colorimetric properties of specific probes for the putative cancer biomarker human arylamine N-acetyltransferase 1.

A naphthoquinone inhibitor of human arylamine N-acetyltransferase 1 (hNAT1), a potential cancer biomarker and therapeutic target, has been reported which undergoes a distinctive concomitant color change from red to blue upon binding to the enzyme. Here we describe the use of in silico modeling alongside structure-activity relationship studies to advance the hit compound towards a potential probe to quantify hNAT1 levels in tissues. Derivatives with both a fifty-fold higher potency against hNAT1 and a two-fold greater absorption coefficient compared to the initial hit have been synthesized; these compounds retain specificity for hNAT1 and its murine homologue mNat2 over the isoenzyme hNAT2.

Mechanism-based inhibition of HsaD: a C-C bond hydrolase essential for survival of Mycobacterium tuberculosis in macrophage.

Mycobacterium tuberculosis remains the leading cause of death by a bacterial pathogen worldwide. Increasing prevalence of multidrug-resistant organisms means prioritizing identification of targets for antituberculars. 2-hydroxy-6-oxo-6-phenylhexa-2,4-dienoate hydrolase (HsaD), part of the cholesterol metabolism operon, is vital for survival within macrophage.

A novel color change mechanism for breast cancer biomarker detection: naphthoquinones as specific ligands of human arylamine N-acetyltransferase 1.

Human arylamine N-acetyltransferase 1 (hNAT1) has become an attractive potential biomarker for estrogen-receptor-positive breast cancers. We describe here the mechanism of action of a selective non-covalent colorimetric biosensor for the recognition of hNAT1 and its murine homologue, mNat2, over their respective isoenzymes, leading to new opportunities in diagnosis. On interaction with the enzyme, the naphthoquinone probe undergoes an instantaneous and striking visible color change from red to blue.

Structure of arylamine N-acetyltransferase from Mycobacterium tuberculosis determined by cross-seeding with the homologous protein from M. marinum: triumph over adversity.

Arylamine N-acetyltransferase from Mycobacterium tuberculosis (TBNAT) plays an important role in the intracellular survival of the microorganism inside macrophages. Medicinal chemistry efforts to optimize inhibitors of the TBNAT enzyme have been hampered by the lack of a three-dimensional structure of the enzyme. In this paper, the first structure of TBNAT, determined using a lone crystal produced using cross-seeding with the homologous protein from M.

Design, synthesis and structure-activity relationships of 3,5-diaryl-1H-pyrazoles as inhibitors of arylamine N-acetyltransferase.

The synthesis and inhibitory potencies of a novel series of 3,5-diaryl-1H-pyrazoles as specific inhibitors of prokaryotic arylamine N-acetyltransferase enzymes is described. The series is based on hit compound 1 3,5-diaryl-1H-pyrazole identified from a high-throughout screen that has been carried out previously and found to inhibit the growth of Mycobacterium tuberculosis.

Piperidinols that show anti-tubercular activity as inhibitors of arylamine N-acetyltransferase: an essential enzyme for mycobacterial survival inside macrophages.

Latent M. tuberculosis infection presents one of the major obstacles in the global eradication of tuberculosis (TB). Cholesterol plays a critical role in the persistence of M.

Arylamine N-acetyltransferases--from drug metabolism and pharmacogenetics to identification of novel targets for pharmacological intervention.

Arylamine N-acetyltransferases (NATs) are defined as xenobiotic metabolizing enzymes, adding an acetyl group from acetyl coenzyme A (CoA) to arylamines and arylhydrazines. NATs are found in organisms from bacteria and fungi to vertebrates. Several isoenzymes, often polymorphic, may be present in one organism.

Activation of nitrofurazone by azoreductases: multiple activities in one enzyme.

Azoreductases are well known for azo pro-drug activation by gut flora. We show that azoreductases have a wider role in drug metabolism than previously thought as they can also reduce and hence activate nitrofurazone. Nitrofurazone, a nitroaromatic drug, is a broad spectrum antibiotic which has until now been considered as activated in bacteria by nitroreductases.

Gene expression profiling of primary male breast cancers reveals two unique subgroups and identifies N-acetyltransferase-1 (NAT1) as a novel prognostic biomarker.

Introduction: Male breast cancer (MBC) is a rare and inadequately characterized disease. The aim of the present study was to characterize MBC tumors transcriptionally, to classify them into comprehensive subgroups, and to compare them with female breast cancer (FBC).

Methods: A total of 66 clinicopathologically well-annotated fresh frozen MBC tumors were analyzed using Illumina Human HT-12 bead arrays, and a tissue microarray with 220 MBC tumors was constructed for validation using immunohistochemistry.

Characterization of an oxidoreductase from the arylamine N-acetyltransferase operon in Mycobacterium smegmatis.

Mycobacterium tuberculosis, the most successful bacterial pathogen, causes tuberculosis, a disease that still causes more than 2 million deaths per year. Arylamine N-acetyltransferase is an enzyme that is conserved in most Mycobacterium spp. The nat gene belongs to an operon that is important for the intracellular survival of M.

Improvement of the expression and purification of Mycobacterium tuberculosis arylamine N-acetyltransferase (TBNAT) a potential target for novel anti-tubercular agents.

Arylamine N-acetyltransferase from Mycobacterium tuberculosis (TBNAT) has been proposed as a drug target for latent tuberculosis treatment. The enzyme is essential for the survival of the mycobacterium in macrophages. However, TBNAT has been very difficult to generate as a soluble protein.