Abstract:
:Cysteine peptidases of Entamoeba histolytica (EhCPs) are considered to be important pathogenicity factors. It has been described that under standard axenic culture conditions, only three (ehcp-a1, ehcp-a2 and ehcp-a5) out of approximately 50 cysteine peptidase genes present in the E. histolytica genome are substantially expressed, thus representing the set of major EhCPs. In this study, transcriptional silencing of the major peptidase genes was used to characterize their physiological role in more detail. Analysing the transfectants a fourth major cysteine peptidase activity belonging to EhCP-A7 could be characterized. Neither cytopathic activity nor phagocytosis of erythrocytes was altered in CP-inactivated amoebae. However, a significant difference in haemolytic activity was observed. EhCP-A1 and EhCP-A7 apparently had no influence on haemolytic activity, whereas transfectants silenced for ehcp-a5 as well as those silenced for all major peptidases showed a significant reduction in their haemolytic activity. Furthermore, cells silenced for ehcp-a1 and ehcp-a7 and more effectively cells silenced in all major ehcps were impaired in digesting of phagocytosed erythrocytes. Moreover, amoebae silenced for all major peptidase genes lost the ability to form aggregates of erythrocytes prior to phagocytosis.
journal_name
Mol Microbioljournal_title
Molecular microbiologyauthors
Irmer H,Tillack M,Biller L,Handal G,Leippe M,Roeder T,Tannich E,Bruchhaus Idoi
10.1111/j.1365-2958.2009.06672.xsubject
Has Abstractpub_date
2009-05-01 00:00:00pages
658-67issue
3eissn
0950-382Xissn
1365-2958pii
MMI6672journal_volume
72pub_type
杂志文章abstract::A number of eukaryotic proteins are already known to orchestrate key steps of mRNA metabolism and translation via interactions with the 5' m7GpppN cap. We have characterized a new type of histidine triad (HIT) motif protein (Nhm1) that co-purifies with the cap-binding complex eIF4F of Schizosaccharomyces pombe. Nhm1 i...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1046/j.1365-2958.2002.03151.x
更新日期:2002-10-01 00:00:00
abstract::Synthesis and secretion of the 110kDa haemolysin toxin of Escherichia coli and other pathogenic Gram-negative bacteria are governed by the four genes of the hly operon. We have identified, by transposon mutagenesis, an E. coli cellular locus, hlyT, required for the synthesis and secretion of haemolysin encoded in tran...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.1992.tb02166.x
更新日期:1992-04-01 00:00:00
abstract::When fungi grow on plant or insect surfaces coated with wax polyesters that protect against pathogens, the fungi generally form aerial hyphae to contact the surfaces. Aerial structures such as hyphae and conidiophores are coated with hydrophobins, which are surface-active proteins involved in adhesion to hydrophobic s...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2005.04803.x
更新日期:2005-09-01 00:00:00
abstract::FlhD and FlhC are the transcriptional activators of the flagellar regulon. The heterotetrameric complex formed by these two proteins activates the transcription of the class II flagellar genes. The flagellar regulon consists not only of flagellar genes, but also of the chemotactic genes and some receptor proteins. Rec...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1046/j.1365-2958.2001.02248.x
更新日期:2001-02-01 00:00:00
abstract::Three distinct types of terminal oxidases participate in the aerobic respiratory pathways of Paracoccus denitrificans. Two alternative genes encoding subunit I of the aa3-type cytochrome c oxidase have been isolated before, namely ctaDI and ctaDII. Each of these genes can be expressed separately to complement a double...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.1994.tb00414.x
更新日期:1994-07-01 00:00:00
abstract::Sinorhizobium meliloti is a soil bacterium that invades the root nodules it induces on Medicago sativa, whereupon it undergoes an alteration of its cell cycle and differentiates into nitrogen-fixing, elongated and polyploid bacteroid with higher membrane permeability. In Caulobacter crescentus, a related alphaproteoba...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/mmi.12347
更新日期:2013-10-01 00:00:00
abstract::Neuroinvasive Escherichia coli K1 synthesizes and assembles a polysialic acid capsule virulence factor on the external leaflet of the outer membrane. This capsule functions in pathogenesis by blocking non-immune host defence mechanisms and acting as a relatively non-immunogenic molecular mimic of the polysialic acid c...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1046/j.1365-2958.1997.5651942.x
更新日期:1997-10-01 00:00:00
abstract::The gene encoding a Lon protease homologue has been cloned from Brucella abortus. The putative Brucella abortus Lon shares > 60% amino acid identity with its Escherichia coli counterpart and the recombinant form of this protein restores the capacity of an Escherichia coli lon mutant to resist killing by ultraviolet ir...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1046/j.1365-2958.2000.01726.x
更新日期:2000-02-01 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::Klebsiella pneumoniae strain PAP996 was previously shown to secrete fatty acylated, aggregated (micellar) pullulanase only after the end of exponential growth. Here we show that the closely related strain K21 secretes large amounts of unacylated, non-aggregated (monomeric) pullulanase during exponential growth. Only a...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.1989.tb00196.x
更新日期:1989-04-01 00:00:00
abstract::It is now well established that the sigma S subunit of RNA polymerase is a master regulator in a complex regulatory network that governs the expression of many stationary-phase-inducible genes in Escherichia coli. In this review, more recent findings will be summarized that demonstrate that sigma S also acts as a glob...
journal_title:Molecular microbiology
pub_type: 杂志文章,评审
doi:10.1046/j.1365-2958.1996.511405.x
更新日期:1996-09-01 00:00:00
abstract::Transposases mediate transposition first by binding specific DNA end sequences that define a transposable element and then by organizing protein and DNA into a highly structured and stable nucleoprotein 'synaptic' complex. Synaptic complex assembly is a central checkpoint in many transposition mechanisms. The Tn5 syna...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2006.05471.x
更新日期:2006-12-01 00:00:00
abstract::While Vipp1 (also known as IM30) clearly is essential for proper biogenesis of thylakoid membranes in chloroplasts and cyanobacteria, the exact function of Vipp1/IM30 still remains unclear. The recent in vivo study of Gutu et al. now demonstrates that Vipp1/IM30 forms localized puncta specifically at highly curved mem...
journal_title:Molecular microbiology
pub_type: 评论,杂志文章
doi:10.1111/mmi.13924
更新日期:2018-04-01 00:00:00
abstract::The syrD gene of Pseudomonas syringae pathovar syringae strain B301D-R was characterized and sequenced. The syrD open reading frame is 1695 bp long and encodes a predicted protein, SyrD, of approximately 63 kDa. Database searches revealed that SyrD shares a high degree of similarity with the ATP-binding cassette (ABC)...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.1993.tb01738.x
更新日期:1993-08-01 00:00:00
abstract::DnaA protein (a trans-acting element) and its binding sequence, DnaA-box: (a cis-acting element) are two elements essential for the initiation of chromosomal replication in Escherichia coli and other enteric bacteria. Recently these two elements have been found to be conserved in three Gram-positive bacteria (Bacillus...
journal_title:Molecular microbiology
pub_type: 杂志文章,评审
doi:10.1111/j.1365-2958.1991.tb01967.x
更新日期:1991-11-01 00:00:00
abstract::The majority of characterized bacterial dipeptide permeases (Dpp) are membrane-associated complexes of five proteins belonging to the ABC-transporter family. They have been found to be involved in the uptake of essential amino acids, haem production, chemotaxis and sporulation. A 5.8 kb genomic DNA fragment of the ser...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1046/j.1365-2958.1998.00898.x
更新日期:1998-06-01 00:00:00
abstract::Release factors RF1 and RF2 are required in bacteria for the cleavage of peptidyl-tRNA. A single sequence motif, GGQ, is conserved in all eubacterial, archaebacterial and eukaryotic release factors and may mimic the CCA end of tRNA, although the position of the motif in the crystal structures of human eRF1 and Escheri...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1046/j.1365-2958.2003.03301.x
更新日期:2003-01-01 00:00:00
abstract::The Bacillus subtilis GlnR transcription factor regulates gene expression in response to changes in nitrogen availability. Glutamine synthetase transmits the nitrogen regulatory signal to GlnR. The DNA-binding activity of GlnR is activated by a transient protein-protein interaction with feedback-inhibited glutamine sy...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2008.06162.x
更新日期:2008-04-01 00:00:00
abstract::Pathogenic enterotoxigenic Escherichia coli (ETEC) are the major bacterial cause of diarrhea in young children in developing countries and in travelers, causing significant mortality in children. Adhesive fimbriae are a prime virulence factor for ETEC, initiating colonization of the small intestinal epithelium. Simila...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/mmi.12847
更新日期:2015-01-01 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::We report selective phosphorylation of the DNA-binding domain of the Streptococcus pneumoniae transcriptional regulator RitR. RitR is annotated as a two-component response regulator, but lacks a cognate His kinase as a neighbouring locus in the genome. In addition, Asn replaces Asp at the expected acceptor site. By th...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2008.06532.x
更新日期:2009-01-01 00:00:00
abstract::Bacterial protein secretion is catalysed by the SecYEG protein-conducting channel complexed with the SecA ATPase motor. To gain insight into the SecA-SecYEG interaction we used peptide arrays, thermodynamic quantification, mutagenesis and functional assays. Our data reveal that: (i) SecA binds with low affinity on sev...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2008.06402.x
更新日期:2008-10-01 00:00:00
abstract::In nitrogen-poor soils, rhizobia elicit nodule formation on legume roots, within which they differentiate into bacteroids that fix atmospheric nitrogen. Protection against reactive oxygen species (ROS) was anticipated to play an important role in Rhizobium-legume symbiosis because nitrogenase is extremely oxygen sensi...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1046/j.1365-2958.2000.02178.x
更新日期:2000-11-01 00:00:00
abstract::BldD generally functions as a repressor controlling morphological development of Streptomyces. In this work, evidences that BldD also activates antibiotic production are provided. In Streptomyces roseosporus (which produces daptomycin widely used for treatment of human infections), deletion of bldD notably reduced dap...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/mmi.14405
更新日期:2020-01-01 00:00:00
abstract::Pseudomonas aeruginosa PAO1, an opportunistic human pathogen, deploys several strategies to resist antibiotics. It uses multidrug efflux pumps, including the MexAB-OprM pump, for antibiotic resistance, and it also produces hydrogen sulfide (H2 S) that provides some defense against antibiotics. MexR functions as a tran...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/mmi.14593
更新日期:2020-12-01 00:00:00
abstract::The opportunistic pathogen Pseudomonas aeruginosa produces type 4 fimbriae which promote adhesion to epithelial cells and are associated with a form of surface translocation called twitching motility. Transposon mutagenesis was used to identify loci required for fimbrial assembly or function by screening for mutants t...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.1995.tb02414.x
更新日期:1995-05-01 00:00:00
abstract::The cell envelope of mycobacteria is a complex multilaminar structure that protects the cell from stresses encountered in the environment, and plays an important role against the bactericidal activity of immune system cells. The outermost layer of the mycobacterial envelope typically contains species-specific glycolip...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2005.04847.x
更新日期:2005-10-01 00:00:00
abstract::Crown gall tumorigenesis by Agrobacterium tumefaciens requires the co-ordinate transcriptional induction of a set of pathogenesis genes. At least three classes of environmental stimuli act synergistically to induce these genes: (i) monocyclic aromatic hydrocarbons such as acetosyringone, coniferyl alcohol, and vanilli...
journal_title:Molecular microbiology
pub_type: 杂志文章,评审
doi:10.1111/j.1365-2958.1991.tb02080.x
更新日期:1991-10-01 00:00:00
abstract::Among the iron-sulphur cluster assembly proteins encoded by gene cluster iscSUA-hscBA-fdx in Escherichia coli, IscA has a unique and strong iron binding activity and can provide iron for iron-sulphur cluster assembly in proteins in vitro. Deletion of IscA and its paralogue SufA results in an E. coli mutant that fails ...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/mmi.12676
更新日期:2014-08-01 00:00:00
abstract::The SaPIs are chromosomal islands in staphylococci and other Gram-positive bacteria that carry genes for superantigens, virulence factors, resistance and certain metabolic functions. They have intimate relationships with certain temperate phages involving phage-induced excision, replication and efficient packaging in ...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2007.06027.x
更新日期:2008-02-01 00:00:00