David Mirelman

Transcriptional Silencing of Multiple Genes in Trophozoites of Entamoeba histolytica (2006)

Rivka Bracha, Yael Nuchamowitz, Michael Anbar, David Mirelman

In a previous work we described the transcriptional silencing of the amoebapore A (AP-A) gene (Ehap-a) of Entamoeba histolytica strain HM-1:IMSS. The silencing occurred following transfection with a...

Entamoeba histolytica Schaudinn, 1903 and Entamoeba dispar Brumpt, 1925: Differences in their Cell Surfaces and in the Bacteria-containing Vacuoles (2002)

LOUIS S. DIAMOND, DAVID MIRELMAN

Entamoeba histolytica Schaudinn, 1903 and Entamoeba dispar Brumpt, 1925 are two of eight species of Entamoeba that sometimes inhabit the human colon. The former is an invasive organism capable of...

Antisense Inhibition of Expression of Cysteine Proteinases Affects Entamoeba histolytica-Induced Formation of Liver Abscess in Hamsters

Ankri, Serge, Stolarsky, Tamara, Bracha, Rivka, Padilla-Vaca, Felipe, Mirelman, David

Trophozoites of virulent Entamoeba histolytica transfected with the antisense gene encoding cysteine proteinase 5 (CP5) have only 10% of the CP activity but retain their cytopathic activity on...

Down Regulation of Entamoeba histolytica Virulence by Monoxenic Cultivation with Escherichia coli O55 Is Related to a Decrease in Expression of the Light (35-Kilodalton) Subunit of the Gal/GalNAc Lectin

Padilla-Vaca, Felipe, Ankri, Serge, Bracha, Rivka, Koole, Lucy Anna, Mirelman, David

Entamoeba histolytica virulence is related to a number of amebic components (lectins, cysteine proteinases, and amebapore) and host factors, such as intestinal bacterial flora. Trophozoites are...

Entamoeba histolytica Expressing a Dominant Negative N-Truncated Light Subunit of Its Gal-Lectin Are Less Virulent

Katz, Uriel, Ankri, Serge, Stolarsky, Tamara, Nuchamowitz, Yael, Mirelman, David

The 260-kDa heterodimeric Gal/GalNAc-specific Lectin (Gal-lectin) of Entamoeba histolytica dissociates under reducing conditions into a heavy (hgl, 170 kDa) and a light subunit (lgl, 35 kDa). We have...

Transcriptional Silencing of an Amoebapore Gene in Entamoeba histolytica: Molecular Analysis and Effect on Pathogenicity

Bracha, Rivka, Nuchamowitz, Yael, Mirelman, David

Transcriptional silencing of the gene coding for amoebapore A (AP-A) was observed when trophozoites of Entamoeba histolytica were transfected with a hybrid plasmid construct containing the ap-a gene...

Nature and Origins of Phosphorus Compounds in Isolated Cell Walls of Staphylococcus aureus

Mirelman, David, Shaw, D. R. D., Park, James T.

Preparations of purified cell walls from Staphylococcus aureus were shown to contain small amounts of phospholipid and glycerol teichoic acid. Since these are components of the cell membrane, it is...

Properties of a Novel Pleiotropic Bacteriophage-Resistant Mutant of Staphylococcus aureus H1

Chatterjee, Anadi N., Mirelman, David, Singer, Howard J., Park, James T.

A phage-resistant mutant of Staphylococcus aureus H (SmR), S. aureus 52A5, was previously shown to lack polymeric teichoic acid. This paper characterizes other phenotypic differences between the...

Improved Filtration Technique for Concentrating and Harvesting Bacteria

Tanny, Gerald B., Mirelman, David, Pistole, Thomas

An improved technique is described for the filtrative concentration and harvesting of bacterial cultures. A pleated tangential flow filtration unit containing 1,000 cm2 of 0.2-μm-pore-size...

Expression of Amoebapores Is Required for Full Expression of Entamoeba histolytica Virulence in Amebic Liver Abscess but Is Not Necessary for the Induction of Inflammation or Tissue Damage in Amebic Colitis

Zhang, Xiaochun, Zhang, Zhi, Alexander, Diane, Bracha, Rivka, Mirelman, David, Stanley, Samuel L.

Entamoeba histolytica trophozoites produce amoebapores, a family of small amphipathic peptides capable of insertion into bacterial or eukaryotic membranes and causing cellular lysis. Recently, E....

Role of the Penicillin-Sensitive Transpeptidation Reaction in Attachment of Newly Synthesized Peptidoglycan to Cell Walls of Micrococcus luteus

Mirelman, David, Bracha, Rivka, Sharon, Nathan

Cell-wall preparations of Micrococcus luteus (lysodeikticus) catalyze in vitro peptidoglycan synthesis from UDP N-acetyl-D-glucosamine, UDP N-acetylmuramic acid-pentapeptide, and glycine. Newly...

Effect of Penicillin on the In Vivo Formation of the d-Alanyl-l-Alanine Peptide Cross-Linkage in Cell Walls of Micrococcus luteus

Mirelman, David, Bracha, Rivka

Penicillin G was found to inhibit the formation of the d-alanyl-l-alanine cross-linkage in intact cells of Micrococcus luteus. This reaction was approximately 50-fold less susceptible to penicillin...

Lectin Activity in Entamoeba histolytica trophozoites

Kobiler, David, Mirelman, David

A lectin (carbohydrate-binding protein) has been found in extracts of a number of axenically grown trophozoites of Entamoeba histolytica strains. The strains grown in TYI-S-33 medium (Diamond et al.,...

Mannose-Binding Activity of Escherichia coli: a Determinant of Attachment and Ingestion of the Bacteria by Macrophages

Bar-Shavit, Zvi, Goldman, Rachel, Ofek, Itzhak, Sharon, Nathan, Mirelman, David

Recently, it was suggested that a mannose-specific lectin on the bacterial cell surface is responsible for the recognition by phagocytic cells of certain nonopsonized Escherichia coli strains. In...

Involvement of a Short Interspersed Element in Epigenetic Transcriptional Silencing of the Amoebapore Gene in Entamoeba histolytica

Anbar, Michael, Bracha, Rivka, Nuchamowitz, Yael, Li, Yan, Florentin, Anat, Mirelman, David

Transcriptional silencing of an amoebapore (ap-a) gene occurred in Entamoeba histolytica following the transfection of plasmids containing a DNA segment (473 bp) homologous to the 5′ upstream...

Transcriptional Silencing of Multiple Genes in Trophozoites of Entamoeba histolytica

Bracha, Rivka, Nuchamowitz, Yael, Anbar, Michael, Mirelman, David

In a previous work we described the transcriptional silencing of the amoebapore A (AP-A) gene (Ehap-a) of Entamoeba histolytica strain HM-1:IMSS. The silencing occurred following transfection with a...

Stress by Heat Shock Induces Massive Down Regulation of Genes and Allows Differential Allelic Expression of the Gal/GalNAc Lectin in Entamoeba histolytica†

Weber, Christian, Guigon, Ghislaine, Bouchier, Christiane, Frangeul, Lionel, Moreira, Sandrine, Sismeiro, Odile, ...

Gene expression analysis by microarray assay revealed that when exposed to stress, Entamoeba histolytica exhibits a specific heat shock response, together with a dramatic overall reduction in gene...

Antimalarial Activity of Allicin, a Biologically Active Compound from Garlic Cloves

Coppi, Alida, Cabinian, Melissa, Mirelman, David, Sinnis, Photini

The incidence of malaria is increasing, and there is an urgent need to identify new drug targets for both prophylaxis and chemotherapy. Potential new drug targets include Plasmodium proteases that...

Antisense Inhibition of Expression of Cysteine Proteinases Affects Entamoeba histolytica-Induced Formation of Liver Abscess in Hamsters

Ankri, Serge, Stolarsky, Tamara, Bracha, Rivka, Padilla-Vaca, Felipe, Mirelman, David

Trophozoites of virulent Entamoeba histolytica transfected with the antisense gene encoding cysteine proteinase 5 (CP5) have only 10% of the CP activity but retain their cytopathic activity on...

Down Regulation of Entamoeba histolytica Virulence by Monoxenic Cultivation with Escherichia coli O55 Is Related to a Decrease in Expression of the Light (35-Kilodalton) Subunit of the Gal/GalNAc Lectin

Padilla-Vaca, Felipe, Ankri, Serge, Bracha, Rivka, Koole, Lucy Anna, Mirelman, David

Entamoeba histolytica virulence is related to a number of amebic components (lectins, cysteine proteinases, and amebapore) and host factors, such as intestinal bacterial flora. Trophozoites are...

Entamoeba histolytica Expressing a Dominant Negative N-Truncated Light Subunit of Its Gal-Lectin Are Less Virulent

Katz, Uriel, Ankri, Serge, Stolarsky, Tamara, Nuchamowitz, Yael, Mirelman, David

The 260-kDa heterodimeric Gal/GalNAc-specific Lectin (Gal-lectin) of Entamoeba histolytica dissociates under reducing conditions into a heavy (hgl, 170 kDa) and a light subunit (lgl, 35 kDa). We have...

Transcriptional Silencing of an Amoebapore Gene in Entamoeba histolytica: Molecular Analysis and Effect on Pathogenicity

Bracha, Rivka, Nuchamowitz, Yael, Mirelman, David

Transcriptional silencing of the gene coding for amoebapore A (AP-A) was observed when trophozoites of Entamoeba histolytica were transfected with a hybrid plasmid construct containing the ap-a gene...

Nature and Origins of Phosphorus Compounds in Isolated Cell Walls of Staphylococcus aureus

Mirelman, David, Shaw, D. R. D., Park, James T.

Preparations of purified cell walls from Staphylococcus aureus were shown to contain small amounts of phospholipid and glycerol teichoic acid. Since these are components of the cell membrane, it is...

Properties of a Novel Pleiotropic Bacteriophage-Resistant Mutant of Staphylococcus aureus H1

Chatterjee, Anadi N., Mirelman, David, Singer, Howard J., Park, James T.

A phage-resistant mutant of Staphylococcus aureus H (SmR), S. aureus 52A5, was previously shown to lack polymeric teichoic acid. This paper characterizes other phenotypic differences between the...

Improved Filtration Technique for Concentrating and Harvesting Bacteria

Tanny, Gerald B., Mirelman, David, Pistole, Thomas

An improved technique is described for the filtrative concentration and harvesting of bacterial cultures. A pleated tangential flow filtration unit containing 1,000 cm2 of 0.2-μm-pore-size...

Expression of Amoebapores Is Required for Full Expression of Entamoeba histolytica Virulence in Amebic Liver Abscess but Is Not Necessary for the Induction of Inflammation or Tissue Damage in Amebic Colitis

Zhang, Xiaochun, Zhang, Zhi, Alexander, Diane, Bracha, Rivka, Mirelman, David, Stanley, Samuel L.

Entamoeba histolytica trophozoites produce amoebapores, a family of small amphipathic peptides capable of insertion into bacterial or eukaryotic membranes and causing cellular lysis. Recently, E....

Role of the Penicillin-Sensitive Transpeptidation Reaction in Attachment of Newly Synthesized Peptidoglycan to Cell Walls of Micrococcus luteus

Mirelman, David, Bracha, Rivka, Sharon, Nathan

Cell-wall preparations of Micrococcus luteus (lysodeikticus) catalyze in vitro peptidoglycan synthesis from UDP N-acetyl-D-glucosamine, UDP N-acetylmuramic acid-pentapeptide, and glycine. Newly...

Effect of Penicillin on the In Vivo Formation of the d-Alanyl-l-Alanine Peptide Cross-Linkage in Cell Walls of Micrococcus luteus

Mirelman, David, Bracha, Rivka

Penicillin G was found to inhibit the formation of the d-alanyl-l-alanine cross-linkage in intact cells of Micrococcus luteus. This reaction was approximately 50-fold less susceptible to penicillin...

Lectin Activity in Entamoeba histolytica trophozoites

Kobiler, David, Mirelman, David

A lectin (carbohydrate-binding protein) has been found in extracts of a number of axenically grown trophozoites of Entamoeba histolytica strains. The strains grown in TYI-S-33 medium (Diamond et al.,...

Mannose-Binding Activity of Escherichia coli: a Determinant of Attachment and Ingestion of the Bacteria by Macrophages

Bar-Shavit, Zvi, Goldman, Rachel, Ofek, Itzhak, Sharon, Nathan, Mirelman, David

Recently, it was suggested that a mannose-specific lectin on the bacterial cell surface is responsible for the recognition by phagocytic cells of certain nonopsonized Escherichia coli strains. In...

Involvement of a Short Interspersed Element in Epigenetic Transcriptional Silencing of the Amoebapore Gene in Entamoeba histolytica

Anbar, Michael, Bracha, Rivka, Nuchamowitz, Yael, Li, Yan, Florentin, Anat, Mirelman, David

Transcriptional silencing of an amoebapore (ap-a) gene occurred in Entamoeba histolytica following the transfection of plasmids containing a DNA segment (473 bp) homologous to the 5′ upstream...

Stress by Heat Shock Induces Massive Down Regulation of Genes and Allows Differential Allelic Expression of the Gal/GalNAc Lectin in Entamoeba histolytica†

Weber, Christian, Guigon, Ghislaine, Bouchier, Christiane, Frangeul, Lionel, Moreira, Sandrine, Sismeiro, Odile, ...

Gene expression analysis by microarray assay revealed that when exposed to stress, Entamoeba histolytica exhibits a specific heat shock response, together with a dramatic overall reduction in gene...

Transcriptional Silencing of Multiple Genes in Trophozoites of Entamoeba histolytica

Bracha, Rivka, Nuchamowitz, Yael, Anbar, Michael, Mirelman, David

In a previous work we described the transcriptional silencing of the amoebapore A (AP-A) gene (Ehap-a) of Entamoeba histolytica strain HM-1:IMSS. The silencing occurred following transfection with a...

Antimalarial Activity of Allicin, a Biologically Active Compound from Garlic Cloves

Coppi, Alida, Cabinian, Melissa, Mirelman, David, Sinnis, Photini

The incidence of malaria is increasing, and there is an urgent need to identify new drug targets for both prophylaxis and chemotherapy. Potential new drug targets include Plasmodium proteases that...

Allicin inhibits SDF-1α-induced T cell interactions with fibronectin and endothelial cells by down-regulating cytoskeleton rearrangement, Pyk-2 phosphorylation and VLA-4 expression

Sela, Uri, Ganor, Sharon, Hecht, Iris, Brill, Alexander, Miron, Talia, Rabinkov, Aharon, ...

Allicin, a major ingredient of fresh garlic extract that is produced during the crushing of garlic cloves, exerts various beneficial biological effects, including a broad spectrum of antimicrobial...

EhLimA, a Novel LIM Protein, Localizes to the Plasma Membrane in Entamoeba histolytica▿

Wender, Nomy, Villalobo, Eduardo, Mirelman, David

The parasitic protozoan Entamoeba histolytica relies on a very dynamic cytoskeleton in order to invade and survive in host tissues. Identification of cytoskeletal elements is key to understanding...

Transcriptional Gene Silencing Reveals Two Distinct Groups of Entamoeba histolytica Gal/GalNAc-Lectin Light Subunits▿

Bracha, Rivka, Nuchamowitz, Yael, Wender, Nomy, Mirelman, David

The Entamoeba histolytica cell surface Gal/GalNAc-inhibitable lectin is a heterodimer between a heavy (170 kDa) subunit linked via a disulfide bond to a light (31 to 35 kDa) subunit. Five light...