[effects of histones on phagocytosis and phagocytic metabolism].enhanced phagocytosis and no intracellular glycogen breakdown was found in guinea-pig peritoneal polymorphonuclear leukocytes (pmn) incubated together with heat-killed staphylococci (twort) treated with a calf thymus histone fraction (p ii), for 1 hr at 37 degrees c. glcose consumption and lactate production of these pmn's were as high as in phagocytosis of the same germ untreated with p ii, and their oxygen consumption was depressed significantly.19761273349
the career of f.w. twort. 19902405283
[kinetic study of the bacteriolysis of staphylococcus aureus twort by its homologous phage]. 19684235707
[mathematical model of the bacteriolysis of staphylococcus aureus twort by its homologous phage]. 19684235708
[use of the phenomenon of alternate lysis of staphylococcus pyogenes aureus (twort) for the study of antiviral substances]. 19674237971
[study of the mutagenic action of nalidixic acid on the twort phage of staphylococcus]. 19694239575
[use of the phenomenon of alternate lysis of staphylococcus pyogenes aureus (twort). ii. action of antiphage serum]. 19684248523
[mutagenic action of nitrofurazone, nitrofurantoin and novobiocin on the phage twort of staphylococcus compared with the activity of mitomycin: general method for study of mutagenic substances]. 19714252045
[analysis of a staphylococcus aureus twort population: growth and modality of dissociation after cell division]. 19684968739
[delysogenization by mutagenic substances, from lysognized staphylococcus twort. comparison between mitomycin c, nalidixic acid, nitrofurazone, nitrofurantoin and novobiocin]. 19714999811
the two-component lysis system of staphylococcus aureus bacteriophage twort: a large ttg-start holin and an associated amidase endolysin.the lysis genes of the virulent staphylococcus aureus bacteriophage twort were cloned and their nucleotide sequences determined. the endolysin gene plytw encodes a 53.3-kda protein, whose catalytic site is located in the amino-terminal domain. an enzymatically active fragment (n-terminal 271 amino acids) was overexpressed in escherichia coli and partially purified. the enzyme rapidly cleaves staphylococcal peptidoglycan, and was shown to act as n-acetylmuramoyl-l-alanine amidase (ec s ...19989627962
the polyvalent staphylococcal phage phi 812: its host-range mutants and related phages.ninety-five percent of 782 culture collection strains, as well as hospital strains of staphylococcus aureus subsp. aureus of different provenance and 43% of 89 culture collection strains of different coagulase-negative species of the genus staphylococcus, were found to be sensitive to the polyvalent phage phi 812 or to at least one of its host-range mutants or to the polyvalent phages sk311, phi 131, and u16. thus sensitivity to the polyvalent staphylococcal phages seems to be one of the common ...19989657943
absence of escherichia coli, listeria monocytogenes, and klebsiella pneumoniae antigens within inflammatory bowel disease tissues.escherichia coli, listeria, and streptococcal antigens have been found in crohn's disease tissues. antibodies to klebsiella pneumoniae have been found in patients with inflammatory bowel disease and ankylosing spondylitis. the presence of these bacterial antigens in crohn's granulomas would be of aetiological interest, while their presence in ulcers alone would be more likely to indicate secondary infection.19989930068
multiple enzymatic activities of the murein hydrolase from staphylococcal phage phi11. identification of a d-alanyl-glycine endopeptidase activity.bacteriophage muralytic enzymes degrade the cell wall envelope of staphylococci to release phage particles from the bacterial cytoplasm. murein hydrolases of staphylococcal phages phi11, 80alpha, 187, twort, and phipvl harbor a central domain that displays sequence homology to known n-acetylmuramyl-l-alanyl amidases; however, their precise cleavage sites on the staphylococcal peptidoglycan have thus far not been determined. here we examined the properties of the phi11 enzyme to hydrolyze either ...199910336488
unexpected abundance of self-splicing introns in the genome of bacteriophage twort: introns in multiple genes, a single gene with three introns, and exon skipping by group i ribozymes.analysis of rna that can be labeled with gtp indicates the existence of group i introns in genes of at least three transcriptional classes in the genome of staphylococcus aureus bacteriophage twort. a single orf of 142 amino acids (orf142) is interrupted by three self-splicing group i introns, providing the first example of a phage gene with multiple intron insertions. twort orf142 is encoded in a message that is abundant 15-20 min after infection and is highly similar to a late gene product (or ...199910359829
the role of yersinia enterocolitica and yersinia pseudotuberculosis in granulomatous appendicitis: a histologic and molecular study.granulomatous appendicitis is an enigmatic entity. purported causes include crohn's disease, foreign body reactions, sarcoidosis, and infectious agents; however, most cases remain idiopathic. yersinia enterocolitica (ye) and y. pseudotuberculosis (yp) have been implicated as causes of appendicitis, ileocolitis, and mesenteric adenitis. the authors examined the potential role of ye and yp in granulomatous appendicitis using histologic and molecular methods. forty cases of granulomatous appendicit ...200111257626
two self-splicing group i introns in the ribonucleotide reductase large subunit gene of staphylococcus aureus phage twort.we have recently described three group i introns inserted into a single gene, orf142, of the staphylococcal bacteriophage twort and suggested the presence of at least two additional self-splicing introns in this phage genome. here we report that two previously uncharacterized introns, 429 and 1087 nt in length, interrupt the twort gene coding for the large subunit of ribonucleotide reductase (nrde). reverse transcription-polymerase chain reaction (rt-pcr) of rna isolated from staphylococcus aure ...200211972330
[on morphology of the twort bacteriophage under the electron microscope]. 196313997138
charles claud twort. 195014785175
[antibiotics and bacteriophage lysis. v. fixation and multiplication of twort staphylococcic phage in the presence of streptomycin]. 195014799965
further observations on the gram-twort stain. 195114832703
[bacteriophages as antibacterial agents].bacteriophages are viruses that only infect bacteria. they have played an important role in the development of molecular biology and have been used as anti-bacterial agents. since their independent discovery by twort and d'herelle, they have been extensively used to prevent and treat bacterial infections, mainly in eastern europe and the former soviet union. in western countries this method has been sporadically employed on humans and domesticated animals. however, the discovery and widespread u ...200415143702
prof. f w twort. 195015423501
identification of bacteriophage types and their carriage in staphylococcus aureus.conserved genomic sequences distinctive of staphylococcus aureus phage types 3a, 11, 77, 187 and twort, representative of phage serogroups a, b, f, l and d, were identified and characterized. pcr primers designed for the above sequences were used for development of a multiplex pcr assay which enabled us not only to classify all phages of the international typing set plus 16 additional phages, but also to detect prophages in s. aureus genomes. one to four different prophages were unambiguously de ...200415593413
two self-splicing group i introns interrupt two late transcribed genes of prolate-headed lactobacillus delbrueckii phage jcl1032.two group i introns were detected from the late gene region of the prolate-headed phage jcl1032 of lactobacillus delbrueckii. introns jcl-i1 and jcl-i2 interrupt orf602 and orf1868 encoding a phage terminase large subunit (terl, 69.7 kda) and a putative tape measure protein (tmp, 202 kda), respectively. the introns jcl-i1 (226 bp) and jcl-i2 (322 bp) were efficiently self-spliced in vivo. both introns were classified to the subgroup ia1 having all the conserved structures necessary for splicing, ...200415669111
the complete genomes and proteomes of 27 staphylococcus aureus bacteriophages.bacteriophages are the most abundant life forms in the biosphere. they play important roles in bacterial ecology, evolution, adaptation to new environments, and pathogenesis of human bacterial infections. here, we report the complete genomic sequences, and predicted proteins of 27 bacteriophages of the gram-positive bacterium staphylococcus aureus. comparative nucleotide and protein sequence analysis indicates that these phages are a remarkable source of untapped genetic diversity, encoding 2,17 ...200515788529
the two-component cell lysis genes holwmy and lyswmy of the staphylococcus warneri m phage varphiwmy: cloning, sequencing, expression, and mutational analysis in escherichia coli.from the genome library of staphylococcus warneri m, the two successive cell-lysis genes (holwmy and lytwmy) were cloned and characterized. the lytwmy gene encoded a protein (lyswmy), whose calculated molecular mass and pi were 54 kda and 8.95, respectively. when overproduced in escherichia coli, lyswmy directed a protein of 45 kda (smaller than the predicted molecular mass), having n-terminal 13 residues identical with those predicted from dna. comparative analysis revealed that lyswmy signific ...200515848115
crystallization and preliminary diffraction analysis of a group i ribozyme from bacteriophage i introns are catalytic rnas that are capable of performing a variety of phosphotransesterification reactions including self-splicing and rna cleavage. the reactions are efficient, accurate and dependent only on the presence of guanosine-nucleotide substrate and sufficient magnesium ion to stabilize the structure of the rna. to understand how the group i intron active-site facilitates catalysis, crystals of a 242-nucleotide ribozyme bound to a four-nucleotide product rna have been produced ...200516508095
competition of bacteriophage polypeptides with native replicase proteins for binding to the dna sliding clamp reveals a novel mechanism for dna replication arrest in staphylococcus aureus.bacteriophages have evolved specific mechanisms that redirect bacterial metabolic pathways to the bacteriophage reproduction cycle. in this study, we characterized the bactericidal mechanism of two polypeptides from bacteriophages twort and g1 that target the dna sliding clamp of staphylococcus aureus. the dna sliding clamp, which tethers dna polymerase to its template and thereby confers processivity upon the enzyme, was found to be essential for the viability of s. aureus. expression of polype ...200617010157
structure of a tyrosyl-trna synthetase splicing factor bound to a group i intron rna.the 'rna world' hypothesis holds that during evolution the structural and enzymatic functions initially served by rna were assumed by proteins, leading to the latter's domination of biological catalysis. this progression can still be seen in modern biology, where ribozymes, such as the ribosome and rnase p, have evolved into protein-dependent rna catalysts ('rnpzymes'). similarly, group i introns use rna-catalysed splicing reactions, but many function as rnpzymes bound to proteins that stabilize ...200818172503
classification of myoviridae bacteriophages using protein sequence similarity.we advocate unifying classical and genomic classification of bacteriophages by integration of proteomic data and physicochemical parameters. our previous application of this approach to the entirely sequenced members of the podoviridae fully supported the current phage classification of the international committee on taxonomy of viruses (ictv). it appears that horizontal gene transfer generally does not totally obliterate evolutionary relationships between phages.200919857251
studies on the bacteriophage of d'herelle : viii. the mechanism of lysis of dead bacteria in the presence of bacteriophage.we have been able to confirm the observations of twort as well as of gratia, that dead staphylococcus may undergo lysis if, in addition to a suitable bacteriophage, there is also present live staphylococcus. moreover, we have endeavored to ascertain the mechanism of this phenomenon and have found that in order to elicit it it is necessary to control the numbers of live and dead bacteria in the mixture. an excess of dead bacteria interferes with lysis by adsorbing the bacteriophage before it has ...192719869297
synergism between a novel chimeric lysin and oxacillin protects against infection by methicillin-resistant staphylococcus aureus.staphylococcus aureus is the causative agent of several serious infectious diseases. the emergence of antibiotic-resistant s. aureus strains has resulted in significant treatment difficulties, intensifying the need for new antimicrobial agents. toward this end, we have developed a novel chimeric bacteriophage (phage) lysin that is active against staphylococci, including methicillin-resistant s. aureus (mrsa). the chimeric lysin (called clys) was obtained by fusing the n-terminal catalytic domain ...201020086153
the rôle of the twort-d'herelle phenomenon in epidemics of mouse-typhoid. 192520474852
further observations on the rôle of the twort-d'herelle phenomenon in the epidemic spread of mouse-typhoid. 192520474866
brochothrix thermosphacta bacteriophages feature heterogeneous and highly mosaic genomes and utilize unique prophage insertion sites.brochothrix belongs to the low-gc branch of gram-positive bacteria (firmicutes), closely related to listeria, staphylococcus, clostridium, and bacillus. brochothrix thermosphacta is a nonproteolytic food spoilage organism, adapted to growth in vacuum-packaged meats. we report the first genome sequences and characterization of brochothrix bacteriophages. phage a9 is a myovirus with an 89-nm capsid diameter and a 171-nm contractile tail; it belongs to the spounavirinae subfamily and shares signifi ...201020709901
Characterization of a bacteriophage, isolated from a cow with mastitis, that is lytic against Staphylococcus aureus strains.Methicillin-resistant strains of Staphylococcus aureus (MRSA) are now the most commonly reported antibiotic-resistant bacterium in clinical settings. Therefore, there is an urgent need to develop novel antibacterial agents to control this pathogen. Bacteriophage therapy is a potential alternative treatment for MRSA infections. The objective of this study was characterization of a novel virulent bacteriophage (MSA6) isolated from a cow with mastitis. Electron microscopy showed its resemblance to ...201122045271
microbiological and molecular assessment of bacteriophage isp for the control of staphylococcus aureus.the increasing antibiotic resistance in bacterial populations requires alternatives for classical treatment of infectious diseases and therefore drives the renewed interest in phage therapy. methicillin resistant staphylococcus aureus (mrsa) is a major problem in health care settings and live-stock breeding across the world. this research aims at a thorough microbiological, genomic, and proteomic characterization of s. aureus phage isp, required for therapeutic applications. host range screening ...201121931710
synonymous codon usage in forty staphylococcal phages identifies the factors controlling codon usage variation and the phages suitable for phage therapy.the immergence and dissemination of multidrug-resistant strains of staphylococcus aureus in recent years have expedited the research on the discovery of novel anti-staphylococcal agents promptly. bacteriophages have long been showing tremendous potentialities in curing the infections caused by various pathogenic bacteria including s. aureus. thus far, only a few virulent bacteriophages, which do not carry any toxin-encoding gene but are capable of eradicating staphylococcal infections, were repo ...201223275718
predicting rna structure by multiple template homology modeling.despite the importance of 3d structure to understand the myriad functions of rnas in cells, most rna molecules remain out of reach of crystallographic and nmr methods. however, certain structural information such as base pairing and some tertiary contacts can be determined readily for many rnas by bioinformatics or relatively low cost experiments. further, because rna structure is highly modular, it is possible to deduce local 3d structure from the solved structures of evolutionarily related rna ...201019908374
studies on the twort-d'herelle phenomenon.1. the experiments here reported were carried out with a lytic principle isolated from the feces of normal rabbits. 2. it seems that bacteriophage is constantly present in the feces of caged laboratory rabbits. 3. a lytic filtrate active for strain shiga 73 (in a dilution of 1:1,000,000) and for the typhoid bacillus (in a dilution of 1:1,000), after twenty successive passages with shiga bacillus was active, for its homologous strain, in a dilution of about 1:10,000,000,000 but no longer possesse ...192419868920
the twort-d'herelle phenomenon : ii. lysis and microbic variation.1. when the few individuals still alive in a dissolved culture of bacillus coli are transplanted on slanted agar, a culture results which possesses new characteristics. first observed by bordet and ciuca, this culture received the temporary name of modified coli. in the study described above, we found that this modified coli is very heterogeneous and that its three principal characteristics, resistance to lysis, lysogenic properties, and mucoid growth, are shared among different types of organis ...192219868606
coarse-grained modeling of large rna molecules with knowledge-based potentials and structural filters.understanding the function of complex rna molecules depends critically on understanding their structure. however, creating three-dimensional (3d) structural models of rna remains a significant challenge. we present a protocol (the nucleic acid simulation tool [nast]) for rna modeling that uses an rna-specific knowledge-based potential in a coarse-grained molecular dynamics engine to generate plausible 3d structures. we demonstrate nast's capabilities by using only secondary structure and tertiar ...200919144906
rna splicing: group i intron crystal structures reveal the basis of splice site selection and metal ion catalysis.the group i intron has served as a model for rna catalysis since its discovery 25 years ago. four recently determined high-resolution crystal structures complement extensive biochemical studies on this system. structures of the azoarcus, tetrahymena and bacteriophage twort group i introns mimic different states of the splicing or ribozyme reaction pathway and provide information on splice site selection and metal ion catalysis. the 5'-splice site is selected by formation of a conserved g.u wobbl ...200616697179
2004 asm conference on the new phage biology: the 'phage summit'.in august, more than 350 conferees from 24 countries attended the asm conference on the new phage biology, in key biscayne, florida. this meeting, also called the phage summit, was the first major international gathering in decades devoted exclusively to phage biology. what emerged from the 5 days of the summit was a clear perspective on the explosive resurgence of interest in all aspects of bacteriophage biology. the classic phage systems like lambda and t4, reinvigorated by structural biology, ...200515720541
crystal structure of a phage twort group i ribozyme-product i introns are catalytic rnas capable of orchestrating two sequential phosphotransesterification reactions that result in self-splicing. to understand how the group i intron active site facilitates catalysis, we have solved the structure of an active ribozyme derived from the orf142-i2 intron from phage twort bound to a four-nucleotide product rna at a resolution of 3.6 a. in addition to the three conserved domains characteristic of all group i introns, the twort ribozyme has peripheral ins ...200415580277
the origin of phage virology.the history of bacteriophage (phage) had its start in 1915, when twort isolated an unusual filterable and infectious agent from excrete of patients struck by diarrhoea; this discovery was followed by an analogous, and probably independent, finding of d'hérelle in 1917. for several years phage research made scant progress but great attention was paid to the question of phage nature, which saw the contrast between d'hérelle and bordet's views (living against chemical nature, respectively). this si ...200616791793
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