| chimeric pneumococcal cell wall lytic enzymes reveal important physiological and evolutionary traits. | two novel chimeric pneumococcal cell wall lytic enzymes, named lc7 and cl7, have been constructed by in vitro recombination of the lyta gene encoding the major autolysin (lyta amidase) of streptococcus pneumoniae, a choline-dependent enzyme, and the cpl7 gene encoding the cpl7 lysozyme of phage cp-7, a choline-independent enzyme. in remarkable contrast with previous chimeric constructions, we fused here two genes that lack nucleotide homology. the cl7 enzyme, which contains the n-terminal domain ... | 1991 | 1672313 |
| cloning and expression of gene fragments encoding the choline-binding domain of pneumococcal murein hydrolases. | the cloning in escherichia coli of the 3' moieties of the lyta and cpl-1 genes is described, coding for the c-terminal regions of the lytic amidase of streptococcus pneumoniae and the phage cp-1 lysozyme, respectively. the truncated genes were overexpressed in e. coli and the purified polypeptides showed a great affinity for choline, although they were devoid of cell wall-degrading activity. biochemical and circular dichroism analyses indicated that these are the domains responsible for the spec ... | 1990 | 1973677 |
| cloning, expression and sequence analysis of an endolysin-encoding gene of lactobacillus bulgaricus bacteriophage mv1. | the lysa gene specifying an endolysin of lactobacillus delbrueckii subsp. bulgaricus bacteriophage mv1, was cloned and expressed in escherichia coli. the 4.05-kb restriction fragment containing this gene was analysed by restriction and deletion mapping, and by subcloning. the nucleotide sequence of a 1150-bp fragment coding for an active lysin was determined. the lysa gene consists of 585 bp and codes for a protein of a deduced mr of 21,120, which agrees with the size based on in vivo transcript ... | 1990 | 2227453 |
| modular organization of the lytic enzymes of streptococcus pneumoniae and its bacteriophages. | the nucleotide sequences of genes cpl7 and cpl9 of the streptococcus pneumoniae bacteriophages cp-7 and cp-9, encoding the muramidases cpl-7 and cpl-9, respectively, have been determined. the n-terminal domains of cpl-7 and cpl-9 were virtually identical to that previously reported for the cpl-1 muramidase. the c-terminal domain of the cpl-7 muramidase, however, was different from those of the host amidase and the phage cp-1 and cp-9 lysozymes. whereas all enzymes studied are characterized by re ... | 1990 | 2311937 |
| structural studies of the lysozyme coded by the pneumococcal phage cp-1. conformational changes induced by choline. | the cpl-1 lysozyme coded by the pneumococcal phage cp-1 has been overproduced in escherichia coli under the control of a modified lipoprotein lactose promoter. this result has provided the conditions to analyse the cpl-1 secondary structure by circular dichroism (cd). the cd spectra recorded in the far-ultraviolet region showed, at neutral ph, two minima at 210 nm and 230 nm and a shoulder at 217 nm, whereas two bands at 260 nm and 295 nm were observed in the near-ultraviolet region. it has been ... | 1990 | 2404766 |
| inverted terminal repeats and terminal proteins of the genomes of pneumococcal phages. | the nucleotide (nt) sequence at the ends of the genomes of the streptococcus pneumoniae phages cp-5 and cp-7 has been determined and compared with the corresponding sequence of phage cp-1. the genomes of phages cp-5 and cp-7 have inverted terminal repeats (itrs) 343 and 347 bp long, respectively. in cp-1 dna the itr is 236 bp long and the following 116 bp are 93% homologous. some regions within the itrs are conserved in the three genomes although the complete sequence of the itrs is no more cons ... | 1985 | 3000885 |
| formation of a covalent complex between the terminal protein of pneumococcal bacteriophage cp-1 and 5'-damp. | incubation of extracts of cp-1-infected streptococcus pneumoniae with [alpha-32p]datp produced a labeled treatment with micrococcal nuclease and sensitive to treatment with proteinase k. incubation of the 32p-labeled protein with 5 m piperidine for 4 h at 50 degrees c released 5'-damp, indicating that a covalent complex between the terminal protein and 5'-damp was formed in vitro. when the four deoxynucleoside triphosphates were included in the reaction mixture, a labeled complex of slower elect ... | 1986 | 3081736 |
| studies on the replication of bacteriophage cp-1 dna in streptococcus pneumoniae. | the dna of bacteriophage cp-1 replicates at optimal conditions when cp-1-infected streptococcus pneumoniae was incubated at 30 degrees c. the in vitro formation of the initiation complex between the terminal protein and 5'-damp was only partially inhibited at 37 degrees c whereas an almost complete inhibition of the dna replication was found at this temperature in vivo. aphidicolin inhibited the multiplication of phage cp-1 but not that of dp-4. this drug did not affect the in vitro formation of ... | 1986 | 3152103 |
| cloning, purification, and biochemical characterization of the pneumococcal bacteriophage cp-1 lysin. | cp-1, a small virulent bacteriophage infecting streptococcus pneumoniae, encodes its own lytic enzyme (cpl). a fragment of cp-1 dna containing the gene cpl coding for cpl was cloned and expressed in high amounts in escherichia coli. cpl was purified to electrophoretic homogeneity by using affinity chromatography on choline-sepharose (t. briese and r. hakenbeck, eur. j. biochem. 146:417-427, 1985), and the enzyme showing a mr of 39,000 was characterized as a muramidase. this muramidase required f ... | 1987 | 3298686 |
| molecular evolution of lytic enzymes of streptococcus pneumoniae and its bacteriophages. | a 2.9-kilobase acc i fragment of the dna of the pneumococcal bacteriophage cp-1, containing the cpl gene, hybridizes with the lyta gene encoding the pneumococcal amidase. the nucleotide sequence of the cpl gene of cp-1, encoding a muramidase (cpl), has been determined. the 3' regions of the cpl and lyta coding sequences show considerable nucleotide sequence homology and the carboxyl-terminal domains of the deduced amino acid sequences of these lysins are quite similar: 73 of the carboxyl-termina ... | 1988 | 3422470 |
| isolation and characterization of a new bacteriophage, cp-1, infecting streptococcus pneumoniae. | several pneumococcal phages showing a morphology completely different from those of all other previously found pneumococcal bacteriophages have been isolated. bacteriophage cp-1, one of the phages isolated, showed an irregular hexagonal structure and a short tail of 20 nm. the virion density was 1.46 g/cm3. sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed the presence of nine polypeptides. the polypeptide showing a molecular weight of 39,000 accounted for more than the 90% of t ... | 1981 | 6275103 |
| pneumococcal bacteriophage cp-1 contains a protein bound to the 5' termini of its dna. | the genome of the pneumococcal bacteriophage cp-1 has been isolated as a dna-protein complex. the transfecting activity of this complex is destroyed by treatment with proteolytic enzymes. the dna-protein complexes do not enter into agarose or acrylamide gels and are retained on glass fiber filters. the protein is specifically associated with the two 5' termini of cp-1 dna on the basis of experiments carried out with restriction endonucleases, exonucleases, and radioactive labeling with [gamma-32 ... | 1983 | 6308899 |
| template requirements for initiation of phage phi 29 dna replication in vitro. | the template requirements for the formation of the phi 29 protein p3-damp initiation complex in vitro have been studied. the initiation reaction requires the parental protein p3 but not an intact dna molecule. protein p3-containing fragments from the left- or right-hand dna ends were active as template for formation of the initiation complex provided they had a minimal size: a 26-base-pair-long fragment was active whereas a 10-base-pair-long one was essentially inactive. however, the activity of ... | 1984 | 6320176 |
| protease-sensitive transfection of streptococcus pneumoniae with bacteriophage cp-1 dna. | the transfecting activity of pneumococcal phage cp-1 dna was destroyed by treatment with proteolytic enzymes, although these enzymes did not affect transfection with bacteriophage dp-4 dna. this transfection was stimulated by calcium ions. protease-treated cp-1 dna competes for binding and uptake with transforming pneumococcal dna as well as with transfecting dp-4 dna to approximately the same extent as does untreated cp-1 dna. in addition, [3h]thymidine-labeled cp-1 dna, treated with proteases ... | 1983 | 6355506 |
| nucleotide sequence at the termini of the dna of streptococcus pneumoniae phage cp-1. | the 5' ends of cp-1 dna, which have a covalently linked terminal protein, can be partially unblocked by treatment with 1 m naoh (e. garcia, a. gomez, c. ronda, c. escarmis, and r. lopez (1983) virology 128, 92-104) and labeled with polynucleotide kinase and [gamma-32p]atp. the sequence of the first 444 and 520 nucleotides at the termini of cp-1 dna has been determined. a 236-nucleotide-long inverted terminal repeat was found and, in addition, the 116 nucleotides following the repeat show 93% hom ... | 1984 | 6702104 |
| bacteriophages of streptococcus pneumoniae. | properties of some of the bacteriophages of streptococcus pneumoniae are reviewed. studies with these phages have yielded several interesting observations and results. (1) a simple transfection system that uses dna of mature pneumococcal phages was developed; results of studies utilizing this system have determined the intracellular events that followed infection with these bacteriophages. (2) some pneumococcal phages have shown dependence on the bacterial (host) murein hydrolase for the liberat ... | 1981 | 7020041 |
| nucleotide sequence and transcription of the left early region of streptococcus pneumoniae bacteriophage cp-1 coding for the terminal protein and the dna polymerase. | cp-1 is a small virulent bacteriophage infecting streptococcus pneumoniae. it has a linear, double-stranded genome of about 19 kb that replicates by a protein-priming mechanism. we have determined the nucleotide sequence of the leftmost 4780 bp of the dna of this bacteriophage; computer analysis revealed that this fragment contains seven open reading frames (orfs) which could encode polypeptides containing more than 50 amino acids. the orfs are clustered in two groups separated by noncoding inte ... | 1995 | 7645213 |
| primary structure and functional analysis of the lysis genes of lactobacillus gasseri bacteriophage phi adh. | the lysis genes of the lactobacillus gasseri bacteriophage phi adh were isolated by complementation of a lambda sam mutation in escherichia coli. nucleotide sequencing of a 1,735-bp dna fragment revealed two adjacent coding regions of 342 bp (hol) and 951 bp (lys) in the same reading frame which appear to belong to a common transcriptional unit. proteins corresponding to the predicted gene products, holin (12.9 kda) and lysin (34.7 kda), were identified by in vitro and in vivo expression of the ... | 1995 | 7836307 |
| analysis of the complete nucleotide sequence and functional organization of the genome of streptococcus pneumoniae bacteriophage cp-1. | cp-1, a bacteriophage infecting streptococcus pneumoniae, has a linear double-stranded dna genome, with a terminal protein covalently linked to its 5' ends, that replicates by the protein-priming mechanism. we describe here the complete dna sequence and transcriptional map of the cp-1 genome. these analyses have led to the firm assignment of 10 genes and the localization of 19 additional open reading frames in the 19,345-bp cp-1 dna. striking similarities and differences between some of these pr ... | 1996 | 8648702 |
| in vitro protein-primed initiation of pneumococcal phage cp-1 dna replication occurs at the third 3' nucleotide of the linear template: a stepwise sliding-back mechanism. | phage cp-1 from streptoccocus pneumoniae makes use of a protein-priming mechanism to start replication of its linear dna: the first reaction consists of the addition of 5' damp to a molecule of the primer protein, an initiation event occurring at both dna ends. after elongation of the initiation complex, the primer protein remains linked to the 5' end of the nascent dna chain, and is subsequently referred to as terminal protein (tp). in this paper, using dna-free extracts from cp-1-infected s. p ... | 1996 | 8757800 |
| functional analysis of the two-gene lysis system of the pneumococcal phage cp-1 in homologous and heterologous host cells. | the two lysis genes cph1 and cpl1 of the streptococcus pneumoniae bacteriophage cp-1 coding for holin and lysozyme, respectively, have been cloned and expressed in escherichia coli. synthesis of the cph1 holin resulted in bacterial cell death but not lysis. the cph1 gene was able to complement a lambda sam mutation in the nonsuppressing e. coli hb101 strain to produce phage progeny, suggesting that the holins encoded by both phage genes have analogous functions and that the pneumococcal holin in ... | 1998 | 9440507 |
| pneumococcal bacteriophage cp-1 encodes its own protease essential for phage maturation. | the major capsid protein of the pneumococcal phage cp-1 that accounts for 90% of the total protein found in the purified virions is synthesized by posttranslational processing of the product of the open reading frame (orf) orf9. cloning of different orfs of the cp-1 genome in escherichia coli and streptococcus pneumoniae combined with western blot analysis of the expressed products led to the conclusion that the product of orf13 is an endoprotease that cleaves off the first 48 amino acid residue ... | 1998 | 9525689 |
| crystallization and preliminary x-ray diffraction studies of the complete modular endolysin from cp-1, a phage infecting streptococcus pneumoniae. | endolysin from the phage cp-1 (cpl-1) cleaves the glycosidic beta1,4-bonds between the n-acetylmuramic acid and the n-acetylglucosamine of the pneumococcal cell wall. cpl-1 has been crystallized using the hanging-drop vapour-diffusion method at 291 k. diffraction-quality orthorhombic crystals of the native protein were obtained only after addition of the detergent n-decyl-beta-d-maltoside. crystals belong to space group c222(1), with unit-cell parameters a = 77.949, b = 95.782, c = 129.282 a. di ... | 2002 | 12198311 |
| structural basis for selective recognition of pneumococcal cell wall by modular endolysin from phage cp-1. | pneumococcal bacteriophage-encoded lysins are modular choline binding proteins that have been shown to act as enzymatic antimicrobial agents (enzybiotics) against streptococcal infections. here we present the crystal structures of the free and choline bound states of the cpl-1 lysin, encoded by the pneumococcal phage cp-1. while the catalytic module displays an irregular (beta/alpha)(5)beta(3) barrel, the cell wall-anchoring module is formed by six similar choline binding repeats (chbrs), arrang ... | 2003 | 14527392 |
| pneumococcal lyta autolysin, a potent therapeutic agent in experimental peritonitis-sepsis caused by highly beta-lactam-resistant streptococcus pneumoniae. | the in vitro and in vivo antipneumococcal activities of the main pneumococcal autolysin (lyta) and cpl-1, a lysozyme encoded by phage cp-1, were studied. intraperitoneal therapy with lyta or high-dose cpl-1 remarkably reduced peritoneal bacterial counts (>5 log(10) cfu/ml) compared with those for the controls. after intravenous injection, lyta was the most effective treatment. | 2007 | 17576844 |
| elucidation of the molecular recognition of bacterial cell wall by modular pneumococcal phage endolysin cpl-1. | pneumococcal bacteriophage-encoded lysins are modular proteins that have been shown to act as enzymatic antimicrobial agents (enzybiotics) in treatment of streptococcal infections. the first x-ray crystal structures of the cpl-1 lysin, encoded by the pneumococcal phage cp-1, in complex with three bacterial cell wall peptidoglycan (pg) analogues are reported herein. the cpl-1 structure is folded in two well defined modules, one responsible for anchoring to the pneumococcal cell wall and the other ... | 2007 | 17581815 |
| characterization and genomic analysis of phage asccphi28, a phage of the family podoviridae infecting lactococcus lactis. | bacteriophage asccphi28 infects dairy fermentation strains of lactococcus lactis. this report describes characterization of asccphi28 and its full genome sequence. phage asccphi28 has a prolate head, whiskers, and a short tail (c2 morphotype). this morphology and dna hybridization to l. lactis phage p369 dna showed that asccphi28 belongs to the p034 phage species, a group rarely encountered in the dairy industry. the burst size of asccphi28 was found to be 121 +/- 18 pfu per infected bacterial c ... | 2008 | 18390678 |
| the proteome and interactome of streptococcus pneumoniae phage cp-1. | mass spectrometry analysis of streptococcus pneumoniae bacteriophage cp-1 identified a total of 12 proteins, and proteome-wide yeast two-hybrid screens revealed 17 binary interactions mainly among these structural proteins. on the basis of the resulting linkage map, we suggest an improved structural model of the cp-1 virion. | 2011 | 21515781 |