33 results
Search Results
2. CelI, a noncellulosomal family 9 enzyme from Clostridium thermocellum, is a processive endoglucanase that degrades crystalline cellulose
- Author
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Larisa Rabinovich, Sima Yaron, Harry J. Gilbert, Edward A. Bayer, Raphael Lamed, Yuval Shoham, and Rachel Gilad
- Subjects
Paper ,Molecular Sequence Data ,Cellulase ,Cleavage (embryo) ,Microbiology ,law.invention ,Frameshift mutation ,chemistry.chemical_compound ,law ,Glycoside hydrolase ,Amino Acid Sequence ,Cellulose ,Cloning, Molecular ,Molecular Biology ,chemistry.chemical_classification ,Clostridium ,biology ,Base Sequence ,Sequence Analysis, DNA ,biology.organism_classification ,Enzymes and Proteins ,Recombinant Proteins ,Enzyme ,Biochemistry ,chemistry ,biology.protein ,Recombinant DNA ,Clostridium thermocellum ,Crystallization - Abstract
The family 9 cellulase gene celI of Clostridium thermocellum , was previously cloned, expressed, and characterized (G. P. Hazlewood, K. Davidson, J. I. Laurie, N. S. Huskisson, and H. J. Gilbert, J. Gen. Microbiol. 139:307-316, 1993). We have recloned and sequenced the entire celI gene and found that the published sequence contained a 53-bp deletion that generated a frameshift mutation, resulting in a truncated and modified C-terminal segment of the protein. The enzymatic properties of the wild-type protein were characterized and found to conform to those of other family 9 glycoside hydrolases with a so-called theme B architecture, where the catalytic module is fused to a family 3c carbohydrate-binding module (CBM3c); CelI also contains a C-terminal CBM3b. The intact recombinant CelI exhibited high levels of activity on all cellulosic substrates tested, with pH and temperature optima of 5.5 and 70°C, respectively, using carboxymethylcellulose as a substrate. Native CelI was capable of solubilizing filter paper, and the distribution of reducing sugar between the soluble and insoluble fractions suggests that the enzyme acts as a processive cellulase. A truncated form of the enzyme, lacking the C terminal CBM3b, failed to bind to crystalline cellulose and displayed reduced activity toward insoluble substrates. A truncated form of the enzyme, in which both the cellulose-binding CBM3b and the fused CBM3c were removed, failed to exhibit significant levels of activity on any of the substrates examined. This study underscores the general nature of this type of enzymatic theme, whereby the fused CBM3c plays a critical accessory role for the family 9 catalytic domain and changes its character to facilitate processive cleavage of recalcitrant cellulose substrates.
- Published
- 2003
3. Complete genome sequence of the cellulose-degrading bacterium Cellulosilyticum lentocellum.
- Author
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Miller DA, Suen G, Bruce D, Copeland A, Cheng JF, Detter C, Goodwin LA, Han CS, Hauser LJ, Land ML, Lapidus A, Lucas S, Meincke L, Pitluck S, Tapia R, Teshima H, Woyke T, Fox BG, Angert ER, and Currie CR
- Subjects
- Cellulose chemistry, Geologic Sediments microbiology, Industrial Waste, Molecular Sequence Annotation, Molecular Sequence Data, Paper, RNA, Bacterial genetics, Rivers, Waste Disposal, Fluid, Water Pollutants, Chemical, Cellulose metabolism, Genome, Bacterial, Gram-Positive Endospore-Forming Rods classification, Gram-Positive Endospore-Forming Rods genetics
- Abstract
Cellulosilyticum lentocellum DSM 5427 is an anaerobic, endospore-forming member of the Firmicutes. We describe the complete genome sequence of this cellulose-degrading bacterium, which was originally isolated from estuarine sediment of a river that received both domestic and paper mill waste. Comparative genomics of cellulolytic clostridia will provide insight into factors that influence degradation rates.
- Published
- 2011
- Full Text
- View/download PDF
4. Biosynthesis of the Iron-Transport Compound Enterochelin: Mutants of Escherichia coli Unable to Synthesize 2,3-Dihydroxybenzoate
- Author
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I. G. Young, L Langman, Frank Gibson, and R. K. J. Luke
- Subjects
Electrophoresis ,Genetics, Microbial ,Paper ,Cyclohexanecarboxylic Acids ,Ultraviolet Rays ,Physiology and Metabolism ,Iron ,Mutant ,Catechols ,Shikimic Acid ,Dehydrogenase ,Biology ,Iron Chelating Agents ,medicine.disease_cause ,Benzoates ,Microbiology ,Cell-free system ,Serine ,chemistry.chemical_compound ,Biosynthesis ,Transduction, Genetic ,Escherichia coli ,medicine ,Molecular Biology ,Cell-Free System ,Structural gene ,Chromosome Mapping ,Shikimic acid ,Molecular biology ,Culture Media ,Genes ,Biochemistry ,chemistry ,Mutation ,Indicators and Reagents - Abstract
Mutants of Escherichia coli K-12 blocked in each of the three enzymatic reactions between chorismate and 2,3-dihydroxybenzoate, in the pathway leading to the iron-sequestering compound enterochelin, have been isolated and biochemically characterized. The three genes concerned (designated entA, entB and entC ) have been shown to be clustered on the chromosome between purE and gal and to be located near minute 14 by cotransduction with the purE, lip , and fep genes. entA, entB , and entC were shown to be the structural genes for 2,3-dihydro-2,3-dihydroxybenzoate dehydrogenase, 2,3-dihydro-2,3-dihydroxybenzoate synthetase, and isochorismate synthetase, respectively.
- Published
- 1971
5. Assay of Streptomycin by the Paper-Disc Plate Method
- Author
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Y. H. Loo, John Ehrlich, J. M. McGuire, J. C. Sylvester, H. H. Thornberry, George M. Savage, and P. S. Skell
- Subjects
Paper ,Plate method ,medicine.drug_class ,Antibiotics ,Reference Standards ,Biology ,Microbiology ,Streptomycin ,medicine ,Biological Assay ,Molecular Biology ,Reference standards ,Beta lactam antibiotics ,medicine.drug - Published
- 1945
6. Gene Expression After Transformation in Bacillus subtilis
- Author
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Lawrence A. Chasin and Boris Magasanik
- Subjects
DNA, Bacterial ,Electrophoresis ,Paper ,Catabolite repression ,Lyases ,Genetics and Molecular Biology ,Bacillus subtilis ,Biology ,Tritium ,medicine.disease_cause ,Microbiology ,chemistry.chemical_compound ,Transformation, Genetic ,Gene expression ,medicine ,Histidine ,Molecular Biology ,Gene ,Crosses, Genetic ,chemistry.chemical_classification ,Mutation ,biology.organism_classification ,Culture Media ,Transformation (genetics) ,Glucose ,Enzyme ,Genes ,Biochemistry ,chemistry ,Spectrophotometry ,DNA - Abstract
Sensitive assays of histidase activity were used to follow the production of this enzyme as directed by a gene newly introduced into cells of Bacillus subtilis by transformation. Histidase activity can be detected in histidase-negative recipient cells within 1 hr after the addition of deoxyribonucleic acid extracted from histidase-positive donors. Enzyme production continues for one to two additional hours and then ceases. Histidase production in the transformed cells is fully sensitive to catabolite repression. Catabolite repression is rapidly established after transformation of recipient cells that are resistant to this form of regulation.
- Published
- 1970
7. Feedback Inhibition of <scp>l</scp> -Glutamine <scp>d</scp> -Fructose 6-Phosphate Amidotransferase by Uridine Diphosphate N -Acetylglucosamine in Neurospora crassa
- Author
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Akira Endo, Kazuo Kakiki, and Tomomasa Misato
- Subjects
Electrophoresis ,Paper ,Uracil Nucleotides ,Physiology and Metabolism ,Chitin ,Microbiology ,Neurospora ,Feedback ,Neurospora crassa ,chemistry.chemical_compound ,Cell Wall ,Glucosamine ,Hexosephosphates ,Molecular Biology ,Transaminases ,Glutamine amidotransferase ,chemistry.chemical_classification ,Carbon Isotopes ,Binding Sites ,biology ,fungi ,biology.organism_classification ,Anti-Bacterial Agents ,carbohydrates (lipids) ,Uridine diphosphate ,Glucose ,Enzyme ,Uridine diphosphate N-acetylglucosamine ,chemistry ,Biochemistry ,Glucosyltransferases ,Spectrophotometry ,Uracil nucleotide - Abstract
The enzyme, l -glutamine d -fructose 6-phosphate amidotransferase (EC 2.6.1.16) of Neurospora crassa , which catalyzes the formation of glucosamine 6-phosphate was shown to be subject to feedback inhibition by uridine diphosphate N -acetyl- d -glucosamine (UDP-GlcNAc). The conclusion is based on the following observations. UDP-GlcNAc, the direct precursor of chitin, did not accumulate in the cell even when its utilization for the synthesis of cell wall chitin was interrupted by the antibiotic polyoxin D, a competitive inhibitor of the chitin synthetase (EC 2.4.1.16). Furthermore, the cellular level of UDP-GlcNAc rose in a short period of time when the amidotransferase was bypassed in vivo by the addition of glucosamine to the growing medium of the fungus. The amidotransferase was purified from N. crassa approximately 85-fold. Kinetic studies showed that UDP-GlcNAc was a potent and specific inhibitor of the amidotransferase, and that it did not alter the Michaelis constant for either l -glutamine or d -fructose 6-phosphate, suggesting that the inhibitor binds at a site on the enzyme distinct from the active site.
- Published
- 1970
8. CelI, a noncellulosomal family 9 enzyme from Clostridium thermocellum, is a processive endoglucanase that degrades crystalline cellulose.
- Author
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Gilad R, Rabinovich L, Yaron S, Bayer EA, Lamed R, Gilbert HJ, and Shoham Y
- Subjects
- Amino Acid Sequence, Base Sequence, Cellulase chemistry, Cellulase genetics, Cloning, Molecular, Clostridium genetics, Crystallization, Molecular Sequence Data, Paper, Recombinant Proteins metabolism, Sequence Analysis, DNA, Cellulase metabolism, Cellulose metabolism, Clostridium enzymology
- Abstract
The family 9 cellulase gene celI of Clostridium thermocellum, was previously cloned, expressed, and characterized (G. P. Hazlewood, K. Davidson, J. I. Laurie, N. S. Huskisson, and H. J. Gilbert, J. Gen. Microbiol. 139:307-316, 1993). We have recloned and sequenced the entire celI gene and found that the published sequence contained a 53-bp deletion that generated a frameshift mutation, resulting in a truncated and modified C-terminal segment of the protein. The enzymatic properties of the wild-type protein were characterized and found to conform to those of other family 9 glycoside hydrolases with a so-called theme B architecture, where the catalytic module is fused to a family 3c carbohydrate-binding module (CBM3c); CelI also contains a C-terminal CBM3b. The intact recombinant CelI exhibited high levels of activity on all cellulosic substrates tested, with pH and temperature optima of 5.5 and 70 degrees C, respectively, using carboxymethylcellulose as a substrate. Native CelI was capable of solubilizing filter paper, and the distribution of reducing sugar between the soluble and insoluble fractions suggests that the enzyme acts as a processive cellulase. A truncated form of the enzyme, lacking the C terminal CBM3b, failed to bind to crystalline cellulose and displayed reduced activity toward insoluble substrates. A truncated form of the enzyme, in which both the cellulose-binding CBM3b and the fused CBM3c were removed, failed to exhibit significant levels of activity on any of the substrates examined. This study underscores the general nature of this type of enzymatic theme, whereby the fused CBM3c plays a critical accessory role for the family 9 catalytic domain and changes its character to facilitate processive cleavage of recalcitrant cellulose substrates.
- Published
- 2003
- Full Text
- View/download PDF
9. Biosynthesis of the actinomycin chromophore: incorporation of 3-hydroxy-4-methylanthranilic acid into actinomycins by Streptomyces antibioticus
- Author
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Jonathan S. Nishimura, Ellis E. Golub, and Martha A. Ward
- Subjects
Electrophoresis ,Paper ,Microbial Physiology and Metabolism ,Streptomyces antibioticus ,Actinomycin IV ,Biology ,medicine.disease_cause ,Microbiology ,chemistry.chemical_compound ,Biosynthesis ,medicine ,polycyclic compounds ,ortho-Aminobenzoates ,Molecular Biology ,Carbon Isotopes ,Reabsorption ,Tryptophan ,Valine ,Hydrogen Peroxide ,Chromophore ,Hydrogen-Ion Concentration ,Streptomyces ,Biochemistry ,chemistry ,Dactinomycin ,Chromatography, Thin Layer ,Caltech Library Services - Abstract
Actinomycin synthesis by washed mycelia of Streptomyces antibioticus has been conducted in the presence of 3-hydroxy-4-methylanthranilate-( carboxyl - 14 C). Incorporation of this compound into actinomycins has been observed, which constitutes further evidence that 3-hydroxy-4-methylanthranilate is an intermediate in actinomycin biosynthesis. The position of the incorporated label has been determined to be within the actinomycin chromophore, and the label appears to be equally distributed between both halves of the chromophore. Incidental to these findings was the observation that the 14 C-labeled actinomycins were subject to rapid reabsorption by the organism with actinomycin V taken up preferentially to actinomycin IV.
- Published
- 1969
10. Control of colanic acid synthesis
- Author
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J. F. Wilkinson, W. D. Grant, and I. W. Sutherland
- Subjects
Electrophoresis ,Genetics, Microbial ,Paper ,Salmonella typhimurium ,Operon ,Ultraviolet Rays ,Phenylalanine ,Enterobacter ,Centrifugation ,Glucuronates ,Genetics and Molecular Biology ,Biology ,Nucleotide sugar ,medicine.disease_cause ,Microbiology ,Fucose ,chemistry.chemical_compound ,medicine ,Escherichia coli ,Nucleotide ,Isomerases ,Molecular Biology ,chemistry.chemical_classification ,Carbon Isotopes ,Nucleotides ,Phosphotransferases ,Polysaccharides, Bacterial ,Galactose ,Fluorine ,Glucuronic acid ,Nucleotidyltransferases ,Culture Media ,Enzyme ,Glucose ,chemistry ,Biochemistry ,Glucosyltransferases ,Chloroform ,Chromatography, Thin Layer - Abstract
The nucleotide pools of certain mucoid, colanic acid-synthesizing strains of Escherichia coli, Salmonella typhimurium , and Aerobacter cloacae were examined, and in all cases the nucleotide sugars uridine-5′-diphosphate glucose (UDPG), uridine-5′-diphosphate galactose (UDPGal), guanosine-5′-diphosphate fucose (GDPF), and uridine-5′-diphosphate glucuronic acid (UDPGA) were detected. It is postulated that these nucleotide sugars are precursors in the synthesis of colanic acid. The levels of these nucleotide sugars and of the enzymes involved in their synthesis were examined in a number of mucoid strains and compared with the levels found in certain strains which were repressed in the synthesis of colanic acid, only becoming mucoid when grown in the presence of p -fluorophenylalanine (PFA). The levels of UDPG and UDPGal and the enzymes involved in their synthesis were substantially the same in both mucoid and repressed types, but the levels of UDPGA and GDPF and of some of the enzymes involved in their synthesis were much higher in mucoid strains. When repressed strains were grown in the presence of PFA, the levels of UDPGA and GDPF approached those found in mucoid strains. The existence of an operon, containing genes coding for certain key enzymes involved in colanic acid synthesis has been suggested.
- Published
- 1970
11. Regulation of S-adenosylmethionine synthetase in Escherichia coli
- Author
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Ronald C. Greene, Ching-Hsiang Su, and Caroline T. Holloway
- Subjects
Electrophoresis ,Paper ,Threonine ,Norleucine ,Repressor ,Microbiology ,Ligases ,chemistry.chemical_compound ,Adenosine Triphosphate ,Methionine ,Leucine ,Transferases ,Escherichia coli ,Methionine synthase ,Ethionine ,Molecular Biology ,Derepression ,chemistry.chemical_classification ,Growth medium ,Carbon Isotopes ,Chromatography ,biology ,Nucleosides ,Stereoisomerism ,Culture Media ,Enzyme Activation ,Enzyme ,Chloramphenicol ,chemistry ,Biochemistry ,Spectrophotometry ,biology.protein ,Enzymology ,Enzyme Repression ,Toluene - Abstract
Addition of methionine to the growth medium of Escherichia coli K-12 leads to a reduction in the specific activity of S -adenosylmethionine (SAM) synthetase. Thus the enzyme appears to be repressible rather than inducible. Mutant strains (probably metJ − ) are constitutive for SAM synthetase as well as for the methionine biosynthetic enzymes, suggesting that the regulatory systems for these enzymes have at least some elements in common. Cells grown to stationary phase in complete medium, which have low specific activities of the enzymes, were routinely used for derepression experiments. The lag in growth and derepression when these cells are incubated in minimal medium is shortened by threonine. Ethionine, norleucine, and α-methylmethionine are poor substrates or nonsubstrates for SAM synthetase and are ineffective repressors. Selenomethionine, a better substrate for SAM synthetase than methionine, is also slightly more effective at repression than methionine. Although SAM is considered to be a likely candidate for the corepressor in the control of the methionine biosynthetic enzymes, addition of SAM to the growth medium does not cause repression. Measurement of SAM uptake shows that too little is taken into the cells to have a significant effect, even if it were active in the control system.
- Published
- 1970
12. Chemical composition of the cell wall of the H37Ra strain of Mycobacterium tuberculosis
- Author
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P. V. Narasimh Acharya and Dexter S. Goldman
- Subjects
Arabinose ,Electrophoresis ,Paper ,Chromatography, Gas ,Chemical Phenomena ,Physiology and Metabolism ,Tuberculostearic acid ,Muramic acid ,Biology ,Microbiology ,Cell wall ,chemistry.chemical_compound ,Glutamates ,Cell Wall ,Monosaccharide ,Amino Acids ,Molecular Biology ,chemistry.chemical_classification ,Alanine ,Glucosamine ,Autoanalysis ,Pimelic Acids ,Fatty Acids ,Monosaccharides ,Galactose ,Amino Sugars ,Mycobacterium tuberculosis ,Chromatography, Ion Exchange ,Lipids ,Amino acid ,Chemistry ,Microscopy, Electron ,chemistry ,Biochemistry ,Spectrophotometry ,Galactosamine ,Microscopy, Electron, Scanning - Abstract
The cell wall of the H37Ra strain of Mycobacterium tuberculosis was isolated and freed of extraneous noncovalently linked material by a series of extraction and enzymatic procedures. Chemical analysis of the cell wall has revealed the following composition: 22.8% amino acids, principally alanine, glutamate, and diaminopimelate in a molar ratio of 1:1.8:0.8; 24.7% reducing sugars, all in the form of arabinose and galactose in a molar ratio of 2.6:1; and 3.95% amino sugars, all in the form of glucosamine, muramic acid, and galactosamine in a molar ratio of 1:6.6:0.8. About 32.1% of the dry weight of the cell wall is lipid, of this about 55% is in the form of two series of mycolic acids. Each series of mycolic acids contains two homologues differing by 28 mass units. One pair of homologues contains in each a carbonyl function and an unsaturated double bond; the other pair contains two cyclopropane groups in each homologue. The remaining lipids are composed principally of normal saturated fatty acids, including tuberculostearic acid.
- Published
- 1970
13. Phospholipids of Streptococcus faecalis
- Author
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J. M. dos Santos Mota, J.A.F. Op den Kamp, L.L.M. Van Deenen, and Hubertus M. Verheij
- Subjects
Electrophoresis ,Paper ,Chemical Phenomena ,Chromatography, Paper ,Physiology and Metabolism ,Biology ,medicine.disease_cause ,Microbiology ,Enterococcus faecalis ,Phosphates ,chemistry.chemical_compound ,medicine ,Molecular Biology ,Phospholipids ,Phosphatidylglycerol ,Streptococcus ,Streptococcus faecalis ATCC 9790 ,Fatty Acids ,technology, industry, and agriculture ,Phosphorus Isotopes ,biology.organism_classification ,Chromatography, Ion Exchange ,Silicon Dioxide ,Lipids ,Paper chromatography ,Chemistry ,chemistry ,Biochemistry ,Stationary phase ,Spectrophotometry ,Autoradiography ,lipids (amino acids, peptides, and proteins) ,Chromatography, Thin Layer ,Derivative (chemistry) - Abstract
Autoradiograms of total lipid extracts from Streptococcus faecalis ATCC 9790, harvested in the stationary phase from a medium containing 32 P-orthophosphate, showed six major spots. The corresponding compounds were identified as diphosphatidylglycerol (possibly with a penta acyl structure); phosphatidylglycerol; a provisionally identified mixture of alanylphosphatidylglycerol and of the 2′-lysyl-derivative of phosphatidylglycerol; the 3′-lysyl-derivative of phosphatidylglycerol, probably together with some arginylphosphatidylglycerol; a diglucosyl derivative of phosphatidylglycerol; and a compound which was tentatively identified as the 2′,3′-dilysyl derivative of phosphatidylglycerol.
- Published
- 1970
14. A SIMPLE PHENYLALANINE PAPER STRIP METHOD FOR IDENTIFICATION OF PROTEUS STRAINS
- Author
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Arleen Glenn and M. Goldin
- Subjects
Paper ,Bacteriological Techniques ,Phenylalanine ,Biology ,Proteus ,biology.organism_classification ,Microbiology ,Simple (abstract algebra) ,Notes ,Identification (biology) ,Biological system ,Molecular Biology - Published
- 1962
15. Role of lipopolysaccharides in antibiotic resistance and bacteriophage adsorption of Escherichia coli K-12.
- Author
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Tamaki S, Sato T, and Matsuhashi M
- Subjects
- Cell Wall analysis, Chromosome Mapping, Conjugation, Genetic, Electrophoresis, Escherichia coli analysis, Galactose analysis, Glucose analysis, Heptoses analysis, Microbial Sensitivity Tests, Mutation, Paper, Phosphates analysis, Recombination, Genetic, Adsorption, Anti-Bacterial Agents pharmacology, Coliphages, Drug Resistance, Microbial, Escherichia coli drug effects, Genetics, Microbial, Lipopolysaccharides analysis, Lipopolysaccharides isolation & purification
- Abstract
Novobiocin-supersensitive (NS) mutants which could not grow on plates containing 40 mug or less of novobiocin per ml were isolated from Escherichia coli strain JE1011 (derived from E. coli K-12). Most of these NS mutants were found to have incomplete lipopolysaccharides (LPS), and they lack phosphate diester bridges in their backbone structure, with or without total loss of heptose, to which the phosphate diester is linked, and consequently lack external outer-core oligosaccharides. The phosphate diester bridges in the LPS backbone are apparently very important in forming a cell surface structure resistant to the penetration of antibiotics such as novobiocin, spiramycin, and actinomycin D. NS mutants, with incomplete LPS, lacking phosphates in their backbone structure were found to be resistant to phage T4, and those which also lacked heptose were resistant to phages T4 and T7. In contrast to the generally accepted idea that resistances to phages T3, T4, and T7 are linked genetically, no NS mutant was found to be resistant to T3. The possible structures of the receptors for T4 and T7 are discussed. The positions of novobiocin-supersensitive genes on the chromosome of several of the NS mutants defective in LPS were mapped. The genes were designated lpcA (between ara and lac) and lpcB (between 55 min and 60 min). The latter seemed to be a group of several related genes.
- Published
- 1971
- Full Text
- View/download PDF
16. Studies on the pathway of incorporation of 2-aminopurine into the deoxyribonucleic acid of Escherichia coli.
- Author
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Rogan EG and Bessman MJ
- Subjects
- Cell-Free System, Chemical Phenomena, Chemistry, Chromatography, Paper, Chromatography, Thin Layer, Culture Media, DNA Nucleotidyltransferases metabolism, Electrophoresis, Escherichia coli enzymology, Escherichia coli growth & development, Nucleosides biosynthesis, Nucleotides biosynthesis, Paper, Phosphorus Isotopes, Phosphotransferases metabolism, RNA Nucleotidyltransferases metabolism, Transferases metabolism, Tritium, DNA, Bacterial biosynthesis, Escherichia coli metabolism, Purines metabolism
- Abstract
A pathway for the incorporation of 2-aminopurine into deoxyribonucleic acid (DNA) was studied in cell-free extracts of Escherichia coli. It was demonstrated that the free base can be converted to the deoxynucleoside, and that the deoxynucleotide can be phosphorylated to the di- and triphosphates and then incorporated into the DNA. From a consideration of the individual reactions in crude extracts, it is likely that the rate-limiting step in this pathway is the formation of the deoxynucleotide. Of especial interest is the observation that 2-aminopurine may be viewed as an analogue of either guanine or adenine, depending on which enzymatic step is being considered. On the one hand, it resembles guanine in that it is specifically converted from the mono- to the diphosphate by guanylate kinase and not by adenylate kinase. On the other hand, it replaces adenine rather than guanine in the DNA synthesized with purified DNA polymerases. E. coli DNA polymerase utilizes aminopurine deoxynucleoside triphosphate as a substrate for DNA synthesis much better than does purified phage T5-induced DNA polymerase and is also much less inhibited by this analogue than the T5 enzyme. These experiments in vitro correlate with known differential effects of 2-aminopurine on E. coli and phage in vivo.
- Published
- 1970
- Full Text
- View/download PDF
17. D-glucaric acid and galactaric acid catabolism by Agrobacterium tumefaciens.
- Author
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Chang YF and Feingold DS
- Subjects
- Carbon Isotopes, Centrifugation, Chromatography, Paper, Chromatography, Thin Layer, Electrophoresis, Glucuronates metabolism, Hydro-Lyases metabolism, Ketoglutaric Acids biosynthesis, NAD pharmacology, Paper, Quaternary Ammonium Compounds, Rhizobium enzymology, Spectrophotometry, Sulfates, Ultraviolet Rays, Adipates metabolism, Rhizobium metabolism
- Abstract
Cell-free extract (crude extract) of Agrobacterium tumefaciens grown on d-glucuronate or d-glucarate converts d-glucarate and galactarate to a mixture of 2-keto-3-deoxy- and 4-deoxy-5-keto-d-glucarate. These compounds are then converted by partially purified crude extract to an intermediate tentatively identified as 2,5-diketoadipate. The same enzyme preparation further decarboxylates this intermediate to alpha-ketoglutarate semialdehyde, which is subsequently oxidized in a nicotinamide adenine dinucleotide-dependent reaction to alpha-ketoglutaric acid. Since A. tumefaciens converts d-glucuronic acid to d-glucarate, a pathway from d-glucuronate to alpha-ketoglutarate in A. tumefaciens was determined.
- Published
- 1970
- Full Text
- View/download PDF
18. A simple phenylalanine paper strip method for identification of Protesus strains.
- Author
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GOLDIN M and GLENN A
- Subjects
- Bacteriological Techniques, Paper, Phenylalanine, Proteus
- Published
- 1962
- Full Text
- View/download PDF
19. Nature and origins of phosphorus compounds in isolated cell walls of Staphylococcus aureus.
- Author
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Mirelman D, Shaw DR, and Park JT
- Subjects
- Acyltransferases metabolism, Autolysis, Bacterial Proteins analysis, Carbon Isotopes, Cell Membrane analysis, Chromatography, Gas, Chromatography, Ion Exchange, Chromatography, Paper, Chromatography, Thin Layer, Electrophoresis, Fatty Acids analysis, Glycerol analysis, Glycerophosphates analysis, Hot Temperature, Hydrolysis, Indicators and Reagents, Lipopolysaccharides analysis, Muramidase, Nucleic Acids analysis, Paper, Phosphorus Isotopes, Polymers, Ribose, Staphylococcus analysis, Staphylococcus enzymology, Transferases metabolism, Cell Wall analysis, Cell Wall enzymology, Glycosides, Pentosephosphates, Phospholipids analysis, Staphylococcus cytology
- Abstract
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 probable that the wall itself contains no lipid, but does retain fragments of membrane because of physical connections between wall and membrane. In walls of S. aureus strain 52A5, which completely lacks ribitol teichoic acid, the only phosphorylated compound identified as a genuine wall component was a phosphorylated derivative of murein that gave rise to muramic acid phosphate on acid hydrolysis. Muramic acid phosphate was also identified in hydrolysates of walls from S. aureus H and strain 52A2.
- Published
- 1971
- Full Text
- View/download PDF
20. Biosynthesis of the actinomycin chromophore: incorporation of 3-hydroxy-4-methylanthranilic acid into actinomycins by Streptomyces antibioticus.
- Author
-
Golub EE, Ward MA, and Nishimura JS
- Subjects
- Carbon Isotopes, Chromatography, Thin Layer, Dactinomycin isolation & purification, Electrophoresis, Hydrogen Peroxide pharmacology, Hydrogen-Ion Concentration, Paper, Tryptophan pharmacology, Valine metabolism, Dactinomycin biosynthesis, Streptomyces metabolism, ortho-Aminobenzoates metabolism
- Abstract
Actinomycin synthesis by washed mycelia of Streptomyces antibioticus has been conducted in the presence of 3-hydroxy-4-methylanthranilate-(carboxyl-(14)C). Incorporation of this compound into actinomycins has been observed, which constitutes further evidence that 3-hydroxy-4-methylanthranilate is an intermediate in actinomycin biosynthesis. The position of the incorporated label has been determined to be within the actinomycin chromophore, and the label appears to be equally distributed between both halves of the chromophore. Incidental to these findings was the observation that the (14)C-labeled actinomycins were subject to rapid reabsorption by the organism with actinomycin V taken up preferentially to actinomycin IV.
- Published
- 1969
- Full Text
- View/download PDF
21. Chemical composition of the cell wall of the H37Ra strain of Mycobacterium tuberculosis.
- Author
-
Acharya PV and Goldman DS
- Subjects
- Alanine analysis, Arabinose analysis, Autoanalysis, Chemical Phenomena, Chemistry, Chromatography, Gas, Chromatography, Ion Exchange, Electrophoresis, Fatty Acids analysis, Galactose analysis, Glucosamine analysis, Glutamates analysis, Microscopy, Electron, Microscopy, Electron, Scanning, Paper, Pimelic Acids analysis, Spectrophotometry, Amino Acids analysis, Amino Sugars analysis, Cell Wall analysis, Lipids analysis, Monosaccharides analysis, Mycobacterium tuberculosis analysis
- Abstract
The cell wall of the H37Ra strain of Mycobacterium tuberculosis was isolated and freed of extraneous noncovalently linked material by a series of extraction and enzymatic procedures. Chemical analysis of the cell wall has revealed the following composition: 22.8% amino acids, principally alanine, glutamate, and diaminopimelate in a molar ratio of 1:1.8:0.8; 24.7% reducing sugars, all in the form of arabinose and galactose in a molar ratio of 2.6:1; and 3.95% amino sugars, all in the form of glucosamine, muramic acid, and galactosamine in a molar ratio of 1:6.6:0.8. About 32.1% of the dry weight of the cell wall is lipid, of this about 55% is in the form of two series of mycolic acids. Each series of mycolic acids contains two homologues differing by 28 mass units. One pair of homologues contains in each a carbonyl function and an unsaturated double bond; the other pair contains two cyclopropane groups in each homologue. The remaining lipids are composed principally of normal saturated fatty acids, including tuberculostearic acid.
- Published
- 1970
- Full Text
- View/download PDF
22. The utilization of thin paper discs in the assay of amylases.
- Author
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SHERWOOD MB
- Subjects
- Humans, Amylases, Biological Assay, Paper
- Published
- 1947
23. Control of colanic acid synthesis.
- Author
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Grant WD, Sutherland IW, and Wilkimson JF
- Subjects
- Carbon Isotopes, Centrifugation, Chloroform, Chromatography, Thin Layer, Culture Media, Electrophoresis, Enterobacter analysis, Enterobacter enzymology, Escherichia coli analysis, Escherichia coli enzymology, Fluorine, Fucose analysis, Galactose analysis, Genetics, Microbial, Glucose analysis, Glucosyltransferases metabolism, Glucuronates analysis, Isomerases metabolism, Nucleotides analysis, Nucleotidyltransferases metabolism, Paper, Phenylalanine, Phosphotransferases metabolism, Salmonella typhimurium analysis, Salmonella typhimurium enzymology, Ultraviolet Rays, Enterobacter metabolism, Escherichia coli metabolism, Polysaccharides, Bacterial biosynthesis, Salmonella typhimurium metabolism
- Abstract
The nucleotide pools of certain mucoid, colanic acid-synthesizing strains of Escherichia coli, Salmonella typhimurium, and Aerobacter cloacae were examined, and in all cases the nucleotide sugars uridine-5'-diphosphate glucose (UDPG), uridine-5'-diphosphate galactose (UDPGal), guanosine-5'-diphosphate fucose (GDPF), and uridine-5'-diphosphate glucuronic acid (UDPGA) were detected. It is postulated that these nucleotide sugars are precursors in the synthesis of colanic acid. The levels of these nucleotide sugars and of the enzymes involved in their synthesis were examined in a number of mucoid strains and compared with the levels found in certain strains which were repressed in the synthesis of colanic acid, only becoming mucoid when grown in the presence of p-fluorophenylalanine (PFA). The levels of UDPG and UDPGal and the enzymes involved in their synthesis were substantially the same in both mucoid and repressed types, but the levels of UDPGA and GDPF and of some of the enzymes involved in their synthesis were much higher in mucoid strains. When repressed strains were grown in the presence of PFA, the levels of UDPGA and GDPF approached those found in mucoid strains. The existence of an operon, containing genes coding for certain key enzymes involved in colanic acid synthesis has been suggested.
- Published
- 1970
- Full Text
- View/download PDF
24. Mechanism of conversion of the salmonella O antigen by bacteriophageepsilon 34.
- Author
-
Wright A
- Subjects
- Carbon Isotopes, Chemical Phenomena, Chemistry, Chromatography, DEAE-Cellulose, Chromatography, Paper, Electron Transport, Electrophoresis, Glucose analysis, Glucose metabolism, Lysogeny, Mutation, Nucleosides pharmacology, Paper, Phosphorus Isotopes, Rhamnose analysis, Salmonella analysis, Salmonella metabolism, Spectrum Analysis, Tritium, Antigens analysis, Lipopolysaccharides analysis, Lipopolysaccharides biosynthesis, Salmonella immunology, Salmonella Phages
- Abstract
The structural determinants for antigen 34 in the E group salmonella are glucosyl substituents on the galactosyl units of the O antigen which has a mannosylrhamnosylgalactose repeating sequence. The temperate bacteriophage epsilon(34) brings about the production of antigen 34. It has been shown here that glucose is transferred from uridine diphosphate glucose to the O antigen via a glucosyl-lipid intermediate in a two-step reaction. Glucose is linked through carbon 1 to the lipid by a phosphodiester bridge, the glucosyl bond having the beta-anomeric configuration. The lipid is a C(55)-polyisoprenoid alcohol, each isoprene unit having one double bond. It is the same lipid which is involved in the synthesis of the O antigen repeating sequence.
- Published
- 1971
- Full Text
- View/download PDF
25. Gene expression after transformation of Bacillus subtilis.
- Author
-
Chasin LA and Magasanik B
- Subjects
- Crosses, Genetic, Culture Media, DNA, Bacterial, Electrophoresis, Glucose, Histidine metabolism, Lyases metabolism, Mutation, Paper, Spectrophotometry, Tritium, Bacillus subtilis enzymology, Bacillus subtilis growth & development, Genes, Lyases biosynthesis, Transformation, Genetic
- Abstract
Sensitive assays of histidase activity were used to follow the production of this enzyme as directed by a gene newly introduced into cells of Bacillus subtilis by transformation. Histidase activity can be detected in histidase-negative recipient cells within 1 hr after the addition of deoxyribonucleic acid extracted from histidase-positive donors. Enzyme production continues for one to two additional hours and then ceases. Histidase production in the transformed cells is fully sensitive to catabolite repression. Catabolite repression is rapidly established after transformation of recipient cells that are resistant to this form of regulation.
- Published
- 1970
- Full Text
- View/download PDF
26. Assay of Streptomycin by the paper-disc plate method.
- Author
-
LOO YH and SKELL PS
- Subjects
- Biological Assay, Paper, Reference Standards, Streptomycin
- Published
- 1945
- Full Text
- View/download PDF
27. Phospholipids of Streptococcus faecalis.
- Author
-
dos Santos Mota JM, den Kamp JA, Verheij HM, and van Deenen LL
- Subjects
- Autoradiography, Chemical Phenomena, Chemistry, Chromatography, Ion Exchange, Chromatography, Paper, Chromatography, Thin Layer, Electrophoresis, Fatty Acids analysis, Lipids analysis, Lipids isolation & purification, Paper, Phosphates metabolism, Phospholipids isolation & purification, Phosphorus Isotopes, Silicon Dioxide, Spectrophotometry, Enterococcus faecalis analysis, Phospholipids analysis
- Abstract
Autoradiograms of total lipid extracts from Streptococcus faecalis ATCC 9790, harvested in the stationary phase from a medium containing (32)P-orthophosphate, showed six major spots. The corresponding compounds were identified as diphosphatidylglycerol (possibly with a penta acyl structure); phosphatidylglycerol; a provisionally identified mixture of alanylphosphatidylglycerol and of the 2'-lysyl-derivative of phosphatidylglycerol; the 3'-lysyl-derivative of phosphatidylglycerol, probably together with some arginylphosphatidylglycerol; a diglucosyl derivative of phosphatidylglycerol; and a compound which was tentatively identified as the 2',3'-dilysyl derivative of phosphatidylglycerol.
- Published
- 1970
- Full Text
- View/download PDF
28. Resistance of Zygorhynchus species to lysis.
- Author
-
Ballesta JP and Alexander M
- Subjects
- Carbohydrates analysis, Carbon Isotopes, Cell Wall analysis, Cell Wall drug effects, Chemical Precipitation, Chromatography, Thin Layer, Culture Media, Electrophoresis, Filtration, Fucose analysis, Fungi analysis, Fungi growth & development, Galactose analysis, Glucosamine analysis, Glucose analysis, Griseofulvin pharmacology, Indicators and Reagents, Infrared Rays, Lignin analysis, Paper, Phosphates analysis, Proteins analysis, Sodium Hydroxide, Soil Microbiology, Solvents, Sorbose pharmacology, Spectrum Analysis, Uronic Acids analysis, Drug Resistance, Microbial, Enzymes pharmacology, Fungi drug effects
- Abstract
Zygorhynchus vuilleminii, a nonmelanin-containing fungus, was not lysed by mycolytic actinomycetes. Several enzymes and Streptomyces enzyme preparations digesting walls of other fungi were without appreciable activity on walls of Zygorhynchus species. A bacterium able to solubilize a portion of the Zygorhynchus wall released little or no reducing sugars from these structures. Fractions of Z. vuilleminii walls were resistant to glucanase hydrolysis, but certain fractions were digested by chitinase and microbial enzyme preparations. The walls and several wall fractions were not readily susceptible to degradation by a soil community. Walls of lysis-resistant Zygorhynchus species contained glucosamine, fucose, glucuronic acid, and galactose but little or no glucose. Resistant wall fractions were rich in uronic acid and fucose, whereas the readily degradable fractions contained abundant glucosamine. Cultural conditions affected the extent of digestion and composition of the walls. Possible reasons for the resistance of Zygorhynchus to lysis in nature are discussed.
- Published
- 1971
- Full Text
- View/download PDF
29. Two mutations in the first gene of the histidine operon of Salmonella typhimurium affecting control.
- Author
-
Rothman-Denes L and Martin RG
- Subjects
- Amino Acids pharmacology, Aspartic Acid metabolism, Aspartic Acid pharmacology, Chromosome Mapping, Culture Media, Drug Resistance, Microbial, Enzyme Repression, Genetics, Microbial, Histidine pharmacology, Microbial Sensitivity Tests, Models, Theoretical, Operon, Paper, Phosphotransferases antagonists & inhibitors, Phosphotransferases metabolism, Recombination, Genetic, Salmonella typhimurium drug effects, Salmonella typhimurium enzymology, Salmonella typhimurium growth & development, Salmonella typhimurium isolation & purification, Spectrophotometry, Transduction, Genetic, Triazoles, Genes, Histidine metabolism, Molecular Biology, Mutation, Salmonella typhimurium metabolism
- Abstract
Two strains with mutations in the first structural gene of the histidine operon of Salmonella typhimurium were characterized. (The first structural gene specifies the first enzyme of histidine biosynthesis, phosphoribosyltransferase, which is sensitive to feedback inhibition by histidine.) One mutation, hisG3934, results in a phosphoribosyltransferase which is no longer sensitive to feedback inhibition by histidine but is instead subject to inhibition by aspartic acid. The other mutation, hisG3935, allows the histidine operon to be partially repressed by several amino acids, including aspartic acid. Analysis of hisG3935 is consistent with the hypothesis that phosphoribosyltransferase is directly involved in the regulation of the histidine operon.
- Published
- 1971
- Full Text
- View/download PDF
30. Heterotrophic growth of blue-gren algae in dim light.
- Author
-
Van Baalen C, Hoare DS, and Brandt E
- Subjects
- Acetates metabolism, Amino Acids metabolism, Autoradiography, Carbon metabolism, Carbon Isotopes, Chromatography, Paper, Culture Media, Cyanobacteria metabolism, Electrophoresis, Glucose metabolism, Paper, Pyruvates metabolism, Cyanobacteria growth & development, Light
- Abstract
A unicellular blue-green alga, Agmenellum quadruplicatum, and a filamentous blue-green alga, Lyngbya lagerheimíi, were grown heterotrophically in dim light with glucose as major source of carbon and possibly energy. The dim-light conditions did not support autotrophic growth. The two blue-green algae appeared to have the same metabolic block, namely an incomplete tricarboxylic acid cycle, as has been found in other obligately phototrophic blue-green algae. Under dim-light conditions, glucose made a greater contribution to cell constituents (amino acids) of A. quadruplicatum and L. lagerheimii than under high-light conditions.
- Published
- 1971
- Full Text
- View/download PDF
31. Feedback inhibition of L-glutamine D-fructose 6-phosphate amidotransferase by uridine diphosphate N-acetylglucosamine in Neurospora crassa.
- Author
-
Endo A, Kakiki K, and Misato T
- Subjects
- Anti-Bacterial Agents pharmacology, Binding Sites, Carbon Isotopes, Cell Wall metabolism, Chitin biosynthesis, Electrophoresis, Feedback, Glucosamine metabolism, Glucose metabolism, Glucosyltransferases antagonists & inhibitors, Hexosephosphates metabolism, Neurospora drug effects, Neurospora metabolism, Paper, Spectrophotometry, Transaminases isolation & purification, Transaminases metabolism, Uracil Nucleotides metabolism, Glucosamine pharmacology, Neurospora enzymology, Transaminases antagonists & inhibitors, Uracil Nucleotides pharmacology
- Abstract
The enzyme, l-glutamine d-fructose 6-phosphate amidotransferase (EC 2.6.1.16) of Neurospora crassa, which catalyzes the formation of glucosamine 6-phosphate was shown to be subject to feedback inhibition by uridine diphosphate N-acetyl-d-glucosamine (UDP-GlcNAc). The conclusion is based on the following observations. UDP-GlcNAc, the direct precursor of chitin, did not accumulate in the cell even when its utilization for the synthesis of cell wall chitin was interrupted by the antibiotic polyoxin D, a competitive inhibitor of the chitin synthetase (EC 2.4.1.16). Furthermore, the cellular level of UDP-GlcNAc rose in a short period of time when the amidotransferase was bypassed in vivo by the addition of glucosamine to the growing medium of the fungus. The amidotransferase was purified from N. crassa approximately 85-fold. Kinetic studies showed that UDP-GlcNAc was a potent and specific inhibitor of the amidotransferase, and that it did not alter the Michaelis constant for either l-glutamine or d-fructose 6-phosphate, suggesting that the inhibitor binds at a site on the enzyme distinct from the active site.
- Published
- 1970
- Full Text
- View/download PDF
32. Biosynthesis of the iron-transport compound enterochelin: mutants of Escherichia coli unable to synthesize 2,3-dihydroxybenzoate.
- Author
-
Young IG, Langman L, Luke RK, and Gibson F
- Subjects
- Benzoates metabolism, Catechols metabolism, Cell-Free System, Chromosome Mapping, Culture Media, Cyclohexanecarboxylic Acids metabolism, Electrophoresis, Escherichia coli growth & development, Genes, Indicators and Reagents, Iron metabolism, Paper, Serine metabolism, Shikimic Acid metabolism, Transduction, Genetic, Ultraviolet Rays, Escherichia coli metabolism, Genetics, Microbial, Iron Chelating Agents biosynthesis, Mutation
- Abstract
Mutants of Escherichia coli K-12 blocked in each of the three enzymatic reactions between chorismate and 2,3-dihydroxybenzoate, in the pathway leading to the iron-sequestering compound enterochelin, have been isolated and biochemically characterized. The three genes concerned (designated entA, entB and entC) have been shown to be clustered on the chromosome between purE and gal and to be located near minute 14 by cotransduction with the purE, lip, and fep genes. entA, entB, and entC were shown to be the structural genes for 2,3-dihydro-2,3-dihydroxybenzoate dehydrogenase, 2,3-dihydro-2,3-dihydroxybenzoate synthetase, and isochorismate synthetase, respectively.
- Published
- 1971
- Full Text
- View/download PDF
33. Regulation of S-adenosylmethionine synthetase in Escherichia coli.
- Author
-
Holloway CT, Greene RC, and Su CH
- Subjects
- Adenosine Triphosphate metabolism, Carbon Isotopes, Chloramphenicol pharmacology, Chromatography, Culture Media, Electrophoresis, Enzyme Activation, Enzyme Repression, Escherichia coli growth & development, Ethionine pharmacology, Leucine pharmacology, Methionine pharmacology, Nucleosides, Paper, Spectrophotometry, Stereoisomerism, Threonine pharmacology, Toluene, Escherichia coli enzymology, Ligases metabolism, Transferases metabolism
- Abstract
Addition of methionine to the growth medium of Escherichia coli K-12 leads to a reduction in the specific activity of S-adenosylmethionine (SAM) synthetase. Thus the enzyme appears to be repressible rather than inducible. Mutant strains (probably metJ(-)) are constitutive for SAM synthetase as well as for the methionine biosynthetic enzymes, suggesting that the regulatory systems for these enzymes have at least some elements in common. Cells grown to stationary phase in complete medium, which have low specific activities of the enzymes, were routinely used for derepression experiments. The lag in growth and derepression when these cells are incubated in minimal medium is shortened by threonine. Ethionine, norleucine, and alpha-methylmethionine are poor substrates or nonsubstrates for SAM synthetase and are ineffective repressors. Selenomethionine, a better substrate for SAM synthetase than methionine, is also slightly more effective at repression than methionine. Although SAM is considered to be a likely candidate for the corepressor in the control of the methionine biosynthetic enzymes, addition of SAM to the growth medium does not cause repression. Measurement of SAM uptake shows that too little is taken into the cells to have a significant effect, even if it were active in the control system.
- Published
- 1970
- Full Text
- View/download PDF
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