Major capsid reinforcement by a minor protein in herpesviruses and phage

To determine the functional specificity of intestinal brush-border pteroylpolyglutamate hydrolase (PPH), we compared the regional location of in vivo hydrolysis of pteroyltriglutamate (PteGlu3) with the location of activity and immunoreactivity of the enzyme in the pig. After in vivo incubations, PteGlu3 hydrolytic products were recovered from intestinal segments in the jejunum but not from the ileum. Brush-border PPH activity in fractionated mucosa was 10-fold greater in the jejunum than in the ileum, whereas the activity of intracellular PPH was increased in the distal ileum. Antibodies to purified brush-border PPH identified a major protein band at 120 kDa and a minor protein band at 195 kDa in solubilized jejunal brush border. Immunohistochemistry identified the enzyme only on the brush-border surface of the jejunum, whereas an immunoblot of solubilized brush-border membranes identified brush-border PPH in the jejunum but not in the ileum. The parallel of the regional location of in vivo hydrolysis of PteGlu3 with the location of brush-border PPH activity and immunoreactivity demonstrates the functional specificity of this enzyme in folate digestion.

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Insertion of a minor protein into the outer membrane of Escherichia coli during inhibition of lipid synthesis.

Journal of Bacteriology ◽

10.1128/jb.122.2.347-351.1975 ◽

1975 ◽

Vol 122 (2) ◽

pp. 347-351 ◽

Cited By ~ 2

Author(s):

L L Randall

Keyword(s):

Escherichia Coli ◽

Outer Membrane ◽

Lipid Synthesis ◽

Minor Protein ◽

A Minor

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A minor, protein-containing galactomannan from a sodium carbonate extract of Cordyceps sinensis

Carbohydrate Research ◽

10.1016/s0008-6215(00)90110-1 ◽

1986 ◽

Vol 156 ◽

pp. 189-197 ◽

Cited By ~ 24

Author(s):

Tadashi Kiho ◽

Hajime Tabata ◽

Shigeo Ukai ◽

Chihiro Hara

Keyword(s):

Sodium Carbonate ◽

Cordyceps Sinensis ◽

Minor Protein ◽

A Minor

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H protein, a minor protein of TMV virions, containssequences of the viral coat protein

Virology ◽

10.1016/s0042-6822(83)80002-6 ◽

1983 ◽

Vol 126 (2) ◽

pp. 429-448 ◽

Cited By ~ 16

Author(s):

Candace Whitmer Collmer ◽

Volker M. Vogt ◽

Milton Zaitlin

Keyword(s):

Coat Protein ◽

Protein A ◽

Viral Coat Protein ◽

Minor Protein ◽

Viral Coat ◽

A Minor ◽

H Protein

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Surface proteins of Plasmodium falciparum merozoites binding to the erythrocyte receptor, glycophorin.

Journal of Experimental Medicine ◽

10.1084/jem.160.3.788 ◽

1984 ◽

Vol 160 (3) ◽

pp. 788-798 ◽

Cited By ~ 58

Author(s):

M E Perkins

Keyword(s):

Specific Binding ◽

Surface Proteins ◽

Malarial Parasite ◽

Ligand Molecule ◽

Glycophorin A ◽

Surface Coat ◽

Receptor Proteins ◽

Erythrocyte Surface ◽

Minor Protein ◽

A Minor

Invasion of erythrocytes by the malarial parasite is a receptor-mediated process. P. falciparum merozoites recognize and bind to erythrocyte surface sialoglycoproteins, glycophorins A and B, and the glycophorins bind to saturable sites on the merozoite surface. The purpose of the present work was to identify a receptor or ligand molecule on the merozoite surface that mediates binding to the erythrocyte. A fraction containing the sialoglycoproteins was coupled to an acrylamide matrix and incubated with metabolically labeled merozoites. A merozoite protein of 155 kD that labeled prominently with [3H]glycine bound to glycophorin. A minor protein of 130 kD also bound. Both proteins are rich in proline and glycine, poor in methionine, and may be related. The proteins are also stable to heating to 100 degrees C for 10 min. Immunoelectron microscopy demonstrated that the 155 kD and 130 kD proteins are located on the merozoite surface coat. The antibodies significantly inhibited merozoite invasion into erythrocytes and also binding of the proteins to the glycophorin-matrix. The specific binding of the 155-kD and 130-kD proteins to the erythrocyte receptor and the demonstration that they are located on the merozoite surface suggest they could be receptor proteins that mediate binding of the merozoite to the erythrocyte surface.

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Vault Poly(ADP-Ribose) Polymerase Is Associated with Mammalian Telomerase and Is Dispensable for Telomerase Function and Vault Structure In Vivo

Molecular and Cellular Biology ◽

10.1128/mcb.24.12.5314-5323.2004 ◽

2004 ◽

Vol 24 (12) ◽

pp. 5314-5323 ◽

Cited By ~ 31

Author(s):

Yie Liu ◽

Bryan E. Snow ◽

Valerie A. Kickhoefer ◽

Natalie Erdmann ◽

Wen Zhou ◽

...

Keyword(s):

Telomere Length ◽

Telomerase Activity ◽

Molecular Assembly ◽

Cellular Functions ◽

Telomere Function ◽

Minor Protein ◽

The Stability ◽

A Minor

ABSTRACT Vault poly(ADP-ribose) polymerase (VPARP) was originally identified as a minor protein component of the vault ribonucleoprotein particle, which may be involved in molecular assembly or subcellular transport. In addition to the association of VPARP with the cytoplasmic vault particle, subpopulations of VPARP localize to the nucleus and the mitotic spindle, indicating that VPARP may have other cellular functions. We found that VPARP was associated with telomerase activity and interacted with exogenously expressed telomerase-associated protein 1 (TEP1) in human cells. To study the possible role of VPARP in telomerase and vault complexes in vivo, mVparp-deficient mice were generated. Mice deficient in mVparp were viable and fertile for up to five generations, with no apparent changes in telomerase activity or telomere length. Vaults purified from mVparp-deficient mouse liver appeared intact, and no defect in association with other vault components was observed. Mice deficient in mTep1, whose disruption alone does not affect telomere function but does affect the stability of vault RNA, showed no additional telomerase or telomere-related phenotypes when the mTep1 deficiency was combined with an mVparp deficiency. These data suggest that murine mTep1 and mVparp, alone or in combination, are dispensable for normal development, telomerase catalysis, telomere length maintenance, and vault structure in vivo.

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Purification of the phosphorylated night form and dephosphorylated day form of phosphoenolpyruvate carboxylase from Bryophyllum fedtschenkoi

Biochemical Journal ◽

10.1042/bj2390213 ◽

1986 ◽

Vol 239 (1) ◽

pp. 213-220 ◽

Cited By ~ 89

Author(s):

G A Nimmo ◽

H G Nimmo ◽

I D Hamilton ◽

C A Fewson ◽

M B Wilkins

Keyword(s):

Phosphoenolpyruvate Carboxylase ◽

Enzyme Concentration ◽

Amino Acid Sequences ◽

Major Protein ◽

Protein Subunit ◽

Minor Protein ◽

Low Sensitivity ◽

A Minor ◽

Related Amino Acid

Phosphoenolpyruvate carboxylase of Bryophyllum fedtschenkoi was shown to exist in two forms: a night form, which is phosphorylated and has low sensitivity to inhibition by malate, and a day form, which is dephosphorylated and 10 times more sensitive to malate. The day and night forms of the enzyme were purified retaining their distinct malate sensitivities and phosphorylation states. The purified enzymes contained a major protein (subunit Mr 112,000) and a minor protein (subunit Mr 123,000). The two polypeptides appeared to have closely related amino acid sequences and were present in a similar ratio in extracts that had been prepared rapidly. The phosphate present in the night form of the enzyme was covalently bound to serine. It was not a catalytic intermediate. Alkaline phosphatase removed the phosphate group in vitro and increased the malate sensitivity of the enzyme to that observed for the day form. Both the day and night forms of the enzyme were probably tetramers, and their apparent Mr was lowered by the presence of malate, but was unaffected by Mg2+ ions, EDTA, a rise in pH or a 10-fold change in enzyme concentration. The rapid loss of malate sensitivity, observed in extracts of leaves prepared during the day and at night, was shown to be due to proteolysis of the enzyme. It was slowed in the presence of malate and by phosphorylation of the enzyme.

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Characterization of Colicin S4 and Its Receptor, OmpW, a Minor Protein of the Escherichia coli Outer Membrane

Journal of Bacteriology ◽

10.1128/jb.181.11.3578-3581.1999 ◽

1999 ◽

Vol 181 (11) ◽

pp. 3578-3581 ◽

Cited By ~ 65

Author(s):

Holger Pilsl ◽

David Smajs ◽

Volkmar Braun

Keyword(s):

Escherichia Coli ◽

Nucleotide Sequence ◽

Receptor Binding ◽

Terminal Region ◽

Receptor Binding Domain ◽

Immunity Protein ◽

Minor Protein ◽

A Minor ◽

Sequence Similarities

ABSTRACT Analysis of the nucleotide sequence of an Escherichia coli colicin S4 determinant revealed 76% identity to the pore-forming domain of the colicin A protein, 77% identity to the colicin A immunity protein, and 82% identity to the colicin A lysis protein. The N-terminal region, which is responsible for the Tol-dependent uptake of colicin S4, has 94% identity to the N-terminal region of colicin K. By contrast, the predicted receptor binding domain shows no sequence similarities to other colicins. Mutants that lacked the OmpW protein were resistant to colicin S4.

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Hydrolysis of fucosyl-GM1 ganglioside by purified pellet-associated human brain and human liver α-l-fucosidases without activator proteins or detergents

Biochemical Journal ◽

10.1042/bj2660491 ◽

1990 ◽

Vol 266 (2) ◽

pp. 491-496 ◽

Cited By ~ 15

Author(s):

R L Hopfer ◽

S W Johnson ◽

M Masserini ◽

A Giuliani ◽

J A Alhadeff

Keyword(s):

Human Brain ◽

Specific Activity ◽

Protein Band ◽

Enzymic Activity ◽

Gm1 Ganglioside ◽

Ph Optimum ◽

Activator Proteins ◽

Minor Protein ◽

A Minor ◽

Triton X

Pellet-associated human brain alpha-L-fucosidase was solubilized with 0.5% (w/v) Triton X-100 and purified by affinity chromatography on agarose-6-aminohexanoyl-fucosamine resin. The procedure resulted in a 290,000-fold purification, a 58% yield and a final specific activity of 11,500 nmol/min per mg of protein. Isoelectric focusing indicated that all six major isoforms (with pI values between 4.1 and 5.3) present in crude brain pellet preparations were purified by the affinity technique. SDS/PAGE indicated the presence of one subunit (54 kDa) and a minor protein band at 67 kDa, which presumably is a contaminant since it was not immunoreactive on Western blotting. The pH optimum of the brain enzyme and its apparent Km for the synthetic substrate 4-methylumbelliferyl alpha-L-fucopyranoside were 5.5 and 0.07 mM respectively. Pellet-associated human brain and liver alpha-L-fucosidases were both capable of hydrolysing fucosyl-GM1 ganglioside without activator proteins or detergents. Linear hydrolysis rates were found only for short incubation times (1-5 min). Optimal enzymic activity at 37 degrees C was found at pH 3.4 for both alpha-L-fucosidases, with no activity at pH values above 4.0.

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Two-dimensional gel electrophoresis can be used to examine chromatographic effluent fractions from displacement column chromatography.

Clinical Chemistry ◽

10.1093/clinchem/28.4.998 ◽

1982 ◽

Vol 28 (4) ◽

pp. 998-999 ◽

Cited By ~ 4

Author(s):

A R Torres ◽

G G Krueger ◽

E A Peterson

Keyword(s):

Human Serum ◽

Column Chromatography ◽

Gel Electrophoresis ◽

Two Dimensional ◽

Two Dimensional Gel Electrophoresis ◽

Gel Method ◽

Minor Protein ◽

Protein Components ◽

A Minor

Abstract We show how two-dimensional gel electrophoresis can be used to monitor protein components in effluent fractions from a displacement column. A minor protein in human serum, of interest in studies on psoriasis and highly enriched by using carboxymethyldextrans as displacers on DEAE-Sephacel, was easily detected in the effluent fractions with the two-dimensional gel method because its concentration was sufficiently high and there was no interference by the carboxymethyldextrans or salt.

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