Abstract:
:Aflatoxins are polyaromatic mycotoxins that contaminate a range of food crops as a result of fungal growth and contribute to serious health problems in the developing world because of their toxicity and mutagenicity. Although relatively resistant to biotic degradation, aflatoxins can be metabolized by certain species of Actinomycetales. However, the enzymatic basis for their breakdown has not been reported until now. We have identified nine Mycobacterium smegmatis enzymes that utilize the deazaflavin cofactor F(420) H(2) to catalyse the reduction of the α,β-unsaturated ester moiety of aflatoxins, activating the molecules for spontaneous hydrolysis and detoxification. These enzymes belong to two previously uncharacterized F(420) H(2) dependent reductase (FDR-A and -B) families that are distantly related to the flavin mononucleotide (FMN) dependent pyridoxamine 5'-phosphate oxidases (PNPOxs). We have solved crystal structures of an enzyme from each FDR family and show that they, like the PNPOxs, adopt a split barrel protein fold, although the FDRs also possess an extended and highly charged F(420) H(2) binding groove. A general role for these enzymes in xenobiotic metabolism is discussed, including the observation that the nitro-reductase Rv3547 from Mycobacterium tuberculosis that is responsible for the activation of bicyclic nitroimidazole prodrugs belongs to the FDR-A family.
journal_name
Mol Microbioljournal_title
Molecular microbiologyauthors
Taylor MC,Jackson CJ,Tattersall DB,French N,Peat TS,Newman J,Briggs LJ,Lapalikar GV,Campbell PM,Scott C,Russell RJ,Oakeshott JGdoi
10.1111/j.1365-2958.2010.07356.xsubject
Has Abstractpub_date
2010-11-01 00:00:00pages
561-75issue
3eissn
0950-382Xissn
1365-2958journal_volume
78pub_type
杂志文章abstract::Lipopolysaccharides (LPS), particularly the O-antigen component, are one of many virulence determinants necessary for Shigella flexneri pathogenesis. O-antigen biosynthesis is determined mostly by genes located in the rfb region of the chromosome. The rfc/wzy gene encodes the O-antigen polymerase, an integral membrane...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1046/j.1365-2958.1998.00884.x
更新日期:1998-06-01 00:00:00
abstract::The non-essential RGD1 gene from Saccharomyces cerevisiae encodes a protein that has been characterized in vitro as a Rho GTPase activating protein (RhoGAP) for the Rho3 and Rho4 proteins. Rgd1p, which displays a conserved FCH-coiled coil-Rho-GAP domain organization, showed a patch-like distribution in the cell, inclu...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1046/j.1365-2958.2000.01958.x
更新日期:2000-06-01 00:00:00
abstract::LeuO is a quiescent LysR-type regulator belonging to the H-NS regulon. Activation of leuO transcription represses expression of pathogenicity island 1 (SPI-1) in Salmonella enterica serovar Typhimurium and inhibits invasion of epithelial cells. Loss of HilE suppresses LeuO-mediated downregulation of SPI-1. Activation ...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/mmi.12500
更新日期:2014-03-01 00:00:00
abstract::Bacteria use quorum-sensing signals or autoinducers to communicate. The signals in Gram-positive bacteria are often peptides activated by proteolytic removal of an N-terminal leader sequence. While investigating stimulation of antimicrobial peptide production by the Streptococcus mutans synthetic competence stimulatin...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2006.05312.x
更新日期:2006-09-01 00:00:00
abstract::In this work, we have studied the in vitro translational features of a bicistronic mRNA of the extremely thermophilic Archaeon Sulfolobus solfataricus, with the aim of determining the nature of the cis-acting signals controlling the recognition of the translation initiation sites in the Archaea. We found that the most...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1046/j.1365-2958.1999.01615.x
更新日期:1999-10-01 00:00:00
abstract::Candida albicans is an opportunistic fungal pathogen. In immunocompromised individuals, it can cause bloodstream infections with high mortality rates. The ability to switch between yeast and hyphal morphologies is a critical virulence factor of C. albicans. In response to diverse environmental cues, several signaling ...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/mmi.14097
更新日期:2018-10-01 00:00:00
abstract::Inhibitors of protein synthesis cause defects in the assembly of ribosomal subunits. In response to treatment with the antibiotics erythromycin or chloramphenicol, precursors of both large and small ribosomal subunits accumulate. We have used a pulse-labelling approach to demonstrate that the accumulating subribosomal...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2011.07555.x
更新日期:2011-04-01 00:00:00
abstract::Malaria transmission requires that the parasites differentiate into gametocytes prior to ingestion by a mosquito during a blood meal. Once in the mosquito midgut the gametocytes emerge from red blood cells (RBCs), fertilize, develop into ookinetes and finally infectious sporozoites. Gamete surface antigen, Pfs230, is ...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2006.05284.x
更新日期:2006-08-01 00:00:00
abstract::The cGvpE protein of Halobacterium salinarum PHH4 has been identified as transcriptional activator for the promoter of the c-gvpA gene encoding the major gas vesicle structural protein cGvpA. Molecular modelling of the carboxy-terminal region of cGvpE suggests that this protein resembles a basic leucine-zipper protein...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1046/j.1365-2958.2002.03031.x
更新日期:2002-07-01 00:00:00
abstract::Whereas tetrahydrofolate is an essential cofactor in all bacteria, the gene that encodes the enzyme dihydrofolate reductase (DHFR) could not be identified in many of the bacteria whose genomes have been entirely sequenced. In this communication we show that the halophilic archaea Halobacterium salinarum and Haloarcula...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2004.04339.x
更新日期:2004-12-01 00:00:00
abstract::Crs5 is a Saccharomyces cerevisiae Metallothionein (MT), non-homologous to the paradigmatic Cu-thionein Cup1. Although considered a secondary copper-resistance agent, we show here that it determines survival under zinc overload in a CUP1-null background. Its overexpression prevents the deleterious effects exhibited by...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2006.05510.x
更新日期:2007-01-01 00:00:00
abstract::The liver stage is the first stage of the malaria parasite that replicates in the vertebrate host. However, little is known about the interplay between the parasite liver stage and its host cell, the hepatocyte. In this study, we identified an exported protein that has a critical role in parasite development in host h...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/mmi.12083
更新日期:2013-01-01 00:00:00
abstract::A family of nine Salmonella typhimurium type III secretion effectors with a conserved amino-terminus have been defined. Three family members (SifA, SifB and SseJ) have previously been demonstrated to localize to the Salmonella-containing vacuole and to Salmonella-induced filaments. In contrast, we demonstrate that two...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1046/j.1365-2958.2003.t01-1-03456.x
更新日期:2003-04-01 00:00:00
abstract::Post-translational proteolysis-dependent regulation of critical cellular processes is a common feature in bacteria. The Escherichia coli Lon protease is involved in the control of the SOS response, acid tolerance and nutritional deprivation. Moreover, Lon plays a role in the regulation of toxin-antitoxin (TA) systems ...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2011.07646.x
更新日期:2011-06-01 00:00:00
abstract::To investigate the possible role of accessory subunits of Escherichia coli DNA polymerase III holoenzyme (HE) in determining chromosomal replication fidelity, we have investigated the role of the dnaX gene. This gene encodes both the tau and gamma subunits of HE, which play a central role in the organization and funct...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2005.05011.x
更新日期:2006-02-01 00:00:00
abstract::Helicobacter pylori persists deep in the human gastric mucus layer in a harsh, nutrient-poor environment. Survival under these conditions depends on the ability of this human pathogen to invoke starvation/stress responses when needed. Unlike many bacteria, H. pylori lacks starvation/stress-responding alternative sigma...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2010.07233.x
更新日期:2010-08-01 00:00:00
abstract::The influence of low pH on inducible gene expression in Lactobacillus acidophilus was investigated by the use of differential display. Logarithmic phase cultures were exposed to pH 3.5 for various intervals, and RNA was isolated and reverse transcribed. The resultant cDNAs were subjected to PCR and the products were r...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1046/j.1365-2958.1999.01557.x
更新日期:1999-09-01 00:00:00
abstract::MisL is an autotransporter protein encoded by Salmonella pathogenicity island 3 (SPI3). To investigate the role of MisL in Salmonella enterica serotype Typhimurium (S. Typhimurium) pathogenesis, we characterized its function during infection of mice and identified a host receptor for this adhesin. In a mouse model of ...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2005.04666.x
更新日期:2005-07-01 00:00:00
abstract::A simplified system using bacterial insertion sequence IS911 has been developed to investigate targeted insertion next to DNA sequences resembling IS ends. We show here that these IR-targeted events occur by an unusual mechanism. In the circular IS911 transposition intermediate the two IRs are abutted to form an IR/IR...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1046/j.1365-2958.2003.03850.x
更新日期:2004-01-01 00:00:00
abstract::Fungal ribotoxins, such as mitogillin and the related Aspergillus toxins restrictocin and alpha-sarcin, are highly specific ribonucleases, which inactivate the ribosome enzymatically by cleaving the eukaryotic 28S RNA of the large ribosomal subunit at a single phosphodiester bond. The site of cleavage occurs between G...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1046/j.1365-2958.1998.00987.x
更新日期:1998-08-01 00:00:00
abstract::Micrococcus luteus secretes a small protein called Rpf, which has autocrine and paracrine signalling functions and is required for the resuscitation of dormant cells. Originally isolated from the supernatant of actively growing cultures, Rpf was also detected on the surface of actively growing bacteria. Most molecules...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1046/j.1365-2958.2002.03183.x
更新日期:2002-11-01 00:00:00
abstract::mscL encodes a channel in Escherichia coli that is opened by membrane stretch force, probably serving as an osmotic gauge. Sequences more or less similar to mscL are found in other bacteria, but the degree of conserved function has been unclear. We subcloned and expressed these putative homologues in E. coli and exami...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1046/j.1365-2958.1998.00821.x
更新日期:1998-05-01 00:00:00
abstract::Type IV secretion systems (T4SS) are utilized by a wide range of Gram negative bacteria to deliver protein and DNA substrates to recipient cells. The best characterized T4SS are the type IVA systems, which exhibit extensive similarity to the Agrobacterium VirB T4SS. In contrast, type IVB secretion systems share almost...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2006.05446.x
更新日期:2006-12-01 00:00:00
abstract::The flagellar genes of Caulobacter crescentus are expressed under cell-cycle control. Expression is regulated by both flagellar assembly cues and cell-cycle events. In this paper we define the sequences required for the expression of the flgF operon, a new class of sigma 54 flagellar promoter. This promoter type is ex...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.1995.tb02300.x
更新日期:1995-04-01 00:00:00
abstract::The unfolded protein response (UPR) is an important stress signalling pathway involved in the cellular development and environmental adaptation of fungi. We investigated the importance of the UPR pathway in the pathogenicity of the plant necrotrophic fungus Alternaria brassicicola, which causes black spot disease on a...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2010.07522.x
更新日期:2011-03-01 00:00:00
abstract::Genes acrAB encode a multidrug efflux pump in Escherichia coli. We have previously reported that transcription of acrAB is increased under general stress conditions (i.e. 4% ethanol, 0.5 M NaCl, and the stationary phase in Luria-Bertani medium). In this study, lacZ transcriptional fusions and an in vitro gel mobility ...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1046/j.1365-2958.1996.357881.x
更新日期:1996-01-01 00:00:00
abstract::Helicobacter pylori strains isolated from most patients with peptic ulcer disease and adenocarcinoma express the vacuolating toxin VacA and contain a pathogenicity island named cag. The cag pathogenicity island codes for more than 40 putative proteins with features similar to bacterial secretion systems. One of these ...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1046/j.1365-2958.1997.5831949.x
更新日期:1997-10-01 00:00:00
abstract::Escherichia coli K-12 strain PS1-28-37 carries the multicopy plasmid pPSO28-37 containing a DNA fragment coding for two of the proteins that enable bacteria to utilize sucrose as sole carbon source. One of the different gene products of the plasmid is the outer membrane protein, ScrY. This protein was isolated and pur...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.1991.tb02153.x
更新日期:1991-09-01 00:00:00
abstract::In contrast to most primary metabolism genes, the genes involved in secondary metabolism and certain nutrient utilization pathways are clustered in fungi. Recently a nuclear protein, LaeA, was found to be required for the transcription of several secondary metabolite gene clusters in Aspergillus nidulans. Here we show...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2006.05330.x
更新日期:2006-09-01 00:00:00
abstract::Trans-acting small regulatory RNAs (sRNAs) are key players in the regulation of gene expression in bacteria. There are hundreds of different sRNAs in a typical bacterium, which in contrast to eukaryotic microRNAs are more heterogeneous in length, sequence composition, and secondary structure. The vast majority of sRNA...
journal_title:Molecular microbiology
pub_type: 杂志文章,评审
doi:10.1111/mmi.14420
更新日期:2020-03-01 00:00:00