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PubMed1973

Isolation of a suppressor host bacterium in Staphylococcus aureus.

A bacterial mutant of Staphylococcus aureus NCTC 8325 has been isolated which has the properties of a suppressor host mutant. The mutant was isolated as a one-step phenotypic revertant to wild type of a strain containing mutations in two unlinked markers concerned with metabolism of lactose via the phosphoenol pyruvate-dependent phosphotransferase system. The revertant (called sup1(+)) has been used to isolate seventy conditional lethal mutants of the phage O11. The phage mutants, which plate on sup1(+) but not on the original 8325 strain, have been assigned by complementation studies into 10 groups. It is probable that this technique for the isolation of suppressor hosts would be applicable to other Staphylococcus strains.

Carbohydrate Metabolism↗

PubMed1977

Transformation in Staphylococcus aureus: role of bacteriophage and incidence of competence among strains.

When used in a helper phage capacity, phages 29, 52, 52A, 79, 80, 55, 71, 53, 83A, 85, 95, 96, phi11, and 80 alpha, all serological group B Staphylococcus phages, conferred competence for transformation to S. aureus 8325-4, a strain that does not normally become competent. Of the serological group A phages tested, only phage 3A showed significant competence-conferring activity. Phages 29, 55, 53, 83A, .85, 95, phi11, and 80 alpha showed an enhancement of competence-conferring activity if exposure to the cells occurred in the presence of nromal rabbit serum. All of the propagating strains for the Staphylococcus reference typing phages were rendered competent for transformation by exposure to at least one of these helper phages. The use of a helper phage to confer competence to S. aureus did not result in distortion of the genetic linkages observed in an inherently competent strain. Lysogenization by phages phi11 or 83A is shown not to be required for the expression of competence, and evidence is presented which indicates that competence in the inherently competent 8325 strain is due to a helper phage effect initiated by the adsorption to cells of phi11 virion parts [or phi11 particles in the case of the single lysogen 8325-4(phi11)] that have been liberated by prophage induction.

Adsorption↗

PubMed1980

Localization of bacteriophage receptor, clumping factor, and protein A on the cell surface of Staphylococcus aureus.

The surface of several laboratory strains of Staphylococcus aureus were observed with a scanning electron microscope, and the presence of two morphologically characteristic structures--a ridge separating cell surface into old and new surfaces and a concentric circular structure--are described. These two structures seemed to be present universally on the surfaces of cells of the genus Staphylococcus. The removal of the circular structures by a mild treatment of the cell with trichloroacetic acid suggested that this structure seemed to represent circularly arranged teichoic acid. With experiments using morphologically recognizable markers among three of the cell wall components, clumping factor, phage receptor, and protein A, the clumping factor was proven to be specifically localized on the old surface; and more phage receptors were detected on the old surface than on the new surface, but protein A was present all over the cell surface. This indicated that the clumping factor and most of the phage receptors appeared on the cell wall surface in a late stage of the cell growth cycle, but protein A was present in an early stage of the growth. The idea of aging of the cell wall is discussed.

Agglutinins↗

PubMed1981

Characterization of a macrolide, lincosamide, and streptogramin resistance plasmid in Staphylococcus epidermidis.

A strain of Staphylococcus epidermidis was transduced to erythromycin resistance, and all of the transductants exhibited the macrolide, lincosamide, streptogramin B resistance phenotype. Curing and antibiotic disk studies also indicated that these resistances were controlled by a single plasmid determinant and were constitutive. Agarose gel electrophoresis of plasmid deoxyribonucleic acid (DNA) from donor, cured, and transduced strains showed that a single plasmid was responsible. This plasmid, designated pNE131, was examined for sequence homology to two other plasmids, pE194 and p1258, from Staphylococcus aureus, which also code for erythromycin resistance. DNA from plasmids pNE131 and pE194 hybridized with one another, but no extensive homology to pI258 with either pNE131 or pE194 was found. Restriction endonuclease digests of pNE131 and pE194 showed no common fragments. However, sequence homology was localized to the nucleotides in pE194 that code for the 29,000-dalton protein responsible for erythromycin resistance. pNE131 was calculated to have 2,220 base pairs and is the smallest naturally occurring plasmid with a known function yet reported in S. epidermidis.

Anti-Bacterial Agents↗

PubMed1982

Arrangement of peptidoglycan in the cell wall of Staphylococcus spp.

The arrangement of peptidoglycan in the cell wall of Staphylococcus was observed with the newly developed freeze-fracture technique, using n-octanol instead of water as the freezing medium. The replica of the trichloroacetic acid-extracted cell wall (TCA-wall) showed two areas. One of them has a concentric circular structure, a characteristic surface structure of the staphylococcal cell wall, and the other showed an irregular and rough surface. The chemical analysis of the wall revealed that the TCA-wall consisted of mostly peptidoglycan. By digesting the TCA-wall with lysozyme, the circular structures were greatly disturbed, and they disappeared after 60 min of treatment. From these observations it can be expected that the peptidoglycan is arranged in a concentric circular manner in the newly generated cell wall of Staphylococcus.

Cell Wall↗

PubMed1984

Secondary structure and phylogeny of Staphylococcus and Micrococcus 5S rRNAs.

Nucleotide sequences of 5S rRNAs from four bacteria, Staphylococcus aureus Smith (diffuse), Staphylococcus epidermidis ATCC 14990, Micrococcus luteus ATCC 9341 and Micrococcus luteus ATCC 4698, were determined. The secondary structural models of S. aureus and S. epidermidis sequences showed characteristics of the gram-positive bacterial 5S rRNA (116-N type [H. Hori and S. Osawa, Proc. Natl. Acad. Sci. U.S.A. 76:381-385, 1979]). Those of M. luteus ATCC 9341 and M. luteus ATCC 4698 together with that of Streptomyces griseus (A. Simoncsits, Nucleic Acids Res. 8:4111-4124, 1980) showed intermediary characteristics between the gram-positive and gram-negative (120-N type [H. Hori and S. Osawa, 1979]) 5S rRNAs. This and previous studies revealed that there exist at least three major groups of eubacteria having distinct 5S rRNA and belonging to different stems in the 5S rRNA phylogenic tree.

Base Sequence↗

PubMed1994

Genetic and biochemical analyses of the biosynthesis of the yellow carotenoid 4,4'-diaponeurosporene of Staphylococcus aureus.

The major pigment produced by Staphylococcus aureus Newman is the deep-yellow carotenoid 4,4'-diaponeurosporene; after prolonged cultivation, this pigment is in part converted to the orange end product staphyloxanthin. From this strain a 3.5-kb DNA fragment was identified which after being cloned into Escherichia coli and Staphylococcus carnosus conferred the ability to produce 4,4'-diaponeurosporene. DNA sequencing of this fragment revealed two open reading frames (ORFs) which are very likely cotranscribed. ORF1 encodes a 254-amino-acid hydrophobic protein, CrtM (M(r), 30,121). The deduced sequence of CrtM exhibits in three domains similarities to the sequences of Saccharomyces cerevisiae and human squalene synthases and phytoene synthases of various bacteria. ORF2 encodes a 448-amino-acid hydrophobic protein, CrtN, with an M(r) of 50,853 whose deduced sequence is similar to those of phytoene desaturases of other bacteria. At the N terminus of CrtN a classical FAD-, NAD(P)-binding domain is found. Spectrophotometry and gas chromatography-mass spectrometry analyses of the carotenoid production of E. coli and S. carnosus clones containing either ORF1 or both ORFs together suggest that ORF1 and ORF2 represent the dehydrosqualene synthase gene (crtM) and the dehydrosqualene desaturase gene (crtN), respectively. The results furthermore suggest that the biosynthesis of 4,4'-diaponeurosporene starts with the condensation of two molecules of farnesyl diphosphate by dehydrosqualene synthase (CrtM); it is shown that the reaction product of this enzyme is dehydrosqualene and not squalene. Dehydrosqualene (4,4'-diapophytoene) is successively dehydrogenated by a desaturase (CrtN) to form the yellow main intermediate 4,4'-diaponeurosporene.

Amino Acid Sequence↗

PubMed1996

Analysis of the Staphylococcus epidermidis genes epiF, -E, and -G involved in epidermin immunity.

The lantibiotic epidermin is produced by Staphylococcus epidermidis Tü3298. The known genes involved in epidermin biosynthesis and regulation are organized as operons (epiABCD and epiQP) that are encoded on the 54-kb plasmid pTü32. Here we describe the characterization of a DNA region that mediates immunity and increased epidermin production, located upstream of the structural gene epiA. The sequence of a 2.6-kb DNA fragment revealed three open reading frames, epiF, -E, and -G, which may form an operon. In the cloning host Staphylococcus carnosus, the three genes mediated an increased tolerance to epidermin, and the highest level of immunity (sevenfold) was achieved with S. carnosus carrying epiFEG and epiQ. The promoter of the first gene, epiF, responded to the activator protein EpiQ and contained a palindromic sequence similar to the EpiQ binding site of the epiA promoter, which is also activated by EpiQ. Inactivation of epiF, -E, or -G resulted in the complete loss of the immunity phenotype. An epidermin-sensitive S. epidermidis Tü3298 mutant was complemented by a DNA fragment containing all three genes. When the epiFEG genes were cloned together with plasmid pTepi14, containing the biosynthetic genes epiABCDQP, the level of epidermin production was approximately fivefold higher. The proteins EpiF, -E, and -G are similar in deduced sequence and proposed structure to the components of various ABC transporter systems. EpiF is a hydrophilic protein with conserved ATP-binding sites, while EpiE and -G have six alternating hydrophobic regions and very likely constitute the integral membrane domains. When EpiF was overproduced in S. carnosus, it was at least partially associated with the cytoplasmic membrane. A potential mechanism for how EpiFEG mediates immunity is discussed.

ATP-Binding Cassette Transporters↗

PubMed1999

Evidence for a holin-like protein gene fully embedded out of frame in the endolysin gene of Staphylococcus aureus bacteriophage 187.

We have cloned, sequenced, and characterized the genes encoding the lytic system of the unique Staphylococcus aureus phage 187. The endolysin gene ply187 encodes a large cell wall-lytic enzyme (71.6 kDa). The catalytic site, responsible for the hydrolysis of staphylococcal peptidoglycan, was mapped to the N-terminal domain of the protein by the expression of defined ply187 domains. This enzymatically active N terminus showed convincing amino acid sequence homology to an N-acetylmuramoyl-L-alanine amidase, whereas the C-terminal part, whose function is unknown, revealed striking relatedness to major staphylococcal autolysins. An additional reading frame was identified entirely embedded out of frame (+1) within the 5' region of ply187 and was shown to encode a small, hydrophobic protein of holin-like function. The hol187 gene features a dual-start motif, possibly enabling the synthesis of two products of different lengths (57 and 55 amino acids, respectively). Overproduction of Hol187 in Escherichia coli resulted in growth retardation, leakiness of the cytoplasmic membrane, and loss of de novo ATP synthesis. Compared to other holins identified to date, Hol187 completely lacks the highly charged C terminus. The secondary structure of the polypeptide is predicted to consist of two small, antiparallel, hydrophobic, transmembrane helices. These are supposed to be essential for integration into the membrane, since site-specific introduction of negatively charged amino acids into the first transmembrane domain (V7D G8D) completely abolished the function of the Hol187 polypeptide. With antibodies raised against a synthetic 18-mer peptide representing a central part of the protein, it was possible to detect Hol187 in the cytoplasmic membrane of phage-infected S. aureus cells. An important indication that the protein actually functions as a holin in vivo was that the gene (but not the V7D G8D mutation) was able to complement a phage lambda Sam mutation in a nonsuppressing E. coli HB101 background. Plaque formation by lambdagt11::hol187 indicated that both phage genes have analogous functions. The data presented here indicate that a putative holin is encoded on a different reading frame within the enzymatically active domain of ply187 and that the holin is synthesized during the late stage of phage infection and found in the cytoplasmic membrane, where it causes membrane lesions which are thought to enable access of Ply187 to the peptidoglycan of phage-infected Staphylococcus cells.

Amino Acid Sequence↗

PubMed2004

Cloning and sequence analysis of genes encoding Staphylococcus hyicus exfoliative toxin types A, B, C, and D.

Exfoliative toxins produced by certain strains of Staphylococcus hyicus mediate exudative epidermitis in pigs. In this study the genes coding for four different exfoliative toxin from S. hyicus (ExhA, ExhB, ExhC, and ExhD) were cloned and sequenced. The coding sequence of the four toxin genes ranged from 816 to 834 bp. The amino acid sequences of these four toxins were homologous to the earlier described exfoliative toxins SHETB from S. hyicus and ETA, ETB, and ETD from Staphylococcus aureus. The homology between the S. hyicus toxins was at the same level as the homology to the exfoliative toxins from S. aureus. The toxins showed similarity to serine proteases, including preservation of the catalytic tract in ExhA, ExhB, and ExhC. However, in ExhD, Asp in the putative catalytic tract was replaced with Glu. The recombinant toxins could be expressed in Escherichia coli, and three of the four toxins were recognized by monoclonal antibodies raised against native exfoliative toxins.

Amino Acid Sequence↗

PubMed2006

The innate immune modulators staphylococcal complement inhibitor and chemotaxis inhibitory protein of Staphylococcus aureus are located on beta-hemolysin-converting bacteriophages.

Two newly discovered immune modulators, chemotaxis inhibitory protein of Staphylococcus aureus (CHIPS) and staphylococcal complement inhibitor (SCIN), cluster on the conserved 3' end of beta-hemolysin (hlb)-converting bacteriophages (betaC-phis). Since these betaC-phis also carry the genes for the immune evasion molecules staphylokinase (sak) and enterotoxin A (sea), this 8-kb region at the 3' end of betaC-phi represents an innate immune evasion cluster (IEC). By PCR and Southern analyses of 85 clinical Staphylococcus aureus strains and 5 classical laboratory strains, we show that 90% of S. aureus strains carry a betaC-phi with an IEC. Seven IEC variants were discovered, carrying different combinations of chp, sak, or sea (or sep), always in the same 5'-to-3' orientation and on the 3' end of a betaC-phi. From most IEC variants we could isolate active bacteriophages by mitomycin C treatment, of which lysogens were generated in S. aureus R5 (broad phage host). All IEC-carrying bacteriophages integrated into hlb, as was measured by Southern blotting of R5 lysogens. Large quantities of the different bacteriophages were obtained by mitomycin C treatment of the lysogens, and bacteriophages were collected and used to reinfect all lysogenic R5 strains. In total, five lytic families were found. Furthermore, phage DNA was isolated and digested with EcoR1, revealing that one IEC variant can be found on different betaI-phis. In conclusion, the four human-specific innate immune modulators SCIN, CHIPS, SAK, and SEA form an IEC that is easily transferred among S. aureus strains by a diverse group of beta-hemolysin-converting bacteriophages.

3' Flanking Region↗

PubMed1961

Antibodies against Staphylococcus aureus in nonimmunized rabbits.

Cohen, Jay O. (Communicable Disease Center, Atlanta, Ga.), Glenda S. Cowart, and William B. Cherry. Antibodies against Staphylococcus aureus in nonimmunized rabbits. J. Bacteriol. 82:110-114. 1961.-Antibody against staphylococci was demonstrated in the serum of each of 36 nonimmunized specific-pathogen-free rabbits that were tested. Evidence obtained is in agreement with the proposition that two distinct staphylococcal antibodies are present in the sera from these nonimmunized rabbits. One is responsible for agglutination of Staphylococcus aureus Cowan serotype I, and the other for the formation of a reaction line observed in Ouchterlony plates with soluble antigens of both Cowan serotype I and Cowan serotype III. Fluorescent antibody reagent prepared from preimmune rabbit serum stained some strains of coagulase positive staphylococci, including Cowan's types I and III, and failed to stain any of 14 coagulase negative strains. The sera of rabbits obtained from a commercial source were shown to contain other antibodies for staphylococci in addition to the two found in the sera of specific-pathogen-free rabbits. The data suggested that rabbits from commercial sources have had contact with a great variety of antigens capable of stimulating staphylococcal antibody.Evidence demonstrated that normal rabbit serum from specific-pathogen-free animals of our colony could be used for differentiation of certain staphylococcal strains.

Animals↗

PubMed1961

Transduction of resistance to chlortetracycline and novobiocin in Staphylococcus aureus.

Pattee, P. A. (Ohio State University, Columbus) and J. N. Baldwin. Transduction of resistance to chlortetracycline and novobiocin in Staphylococcus aureus. J. Bacteriol. 82: 875-881. 1961.-Using phage 80 of the International Typing Series propagated on appropriate strains of Staphylococcus aureus, resistance to chlortetracycline and novobiocin and the capacity to produce penicillinase were transduced to a number of antibiotic-sensitive recipient strains of S. aureus. The frequency of transduction varied from 1 to 10 transductants per 10(7) phage particles employed. Lysogenization of the transductants by the transducing phage did not occur. Phages 29, 52A, 79, and 53 of the International Typing Series were also capable of transduction, while phages 42B and 81 were unable to participate under the conditions used. The recipient strains were either resistant or susceptible to lysis by the transducing phages, but this did not influence the transduction frequencies. Lysis of transductants susceptible to the transducing phages was inhibited by preparing the selective medium with brain heart infusion agar. Linked transductions were not detected. With few exceptions, all of the recipient strains were susceptible to lysis by phages of group I or phage 81 or both. Strains susceptible to lysis by phages of groups II and III, but resistant to lysis by phages of group I or phage 81, were not transduced.

Anti-Bacterial Agents↗

PubMed1962

Effect of pH and inorganic salts on penicillinase formation in Staphylococcus aureus.

Leitner, Felix (Michael Reese Hospital, Chicago, Ill.) and Sidney Cohen. Effect of pH and inorganic salts on penicillinase formation in Staphylococcus aureus. J. Bacteriol. 83:314-323. 1962.-Staphylococcus aureus strain 55-C-1 exhibited a progressive increase in penicillinase activity as the pH of its growth medium dropped from 6.0 to 4.7. At pH 4.7, the increase in enzymic activity was inhibited markedly by Ca(++), somewhat less by Mg(++), and moderately by NaCl, KCl, and NH(4)Cl. Inhibition by NaH(2)PO(4) was greater than by NaCl. Growth at the same pH, in small concentrations of Fe(NH(4))(2)(SO(4))(2) (10(-5) to 10(-6)m), elevated penicillinase activity strikingly, an effect shared to a lesser degree with FeCl(3), CoCl(2), and, very slightly, MnCl(2). The available evidence indicated that the changes in enzymic activity were the result of changes in rate of formation of the enzyme.

Culture Media↗

PubMed1962

Aerobic respiratory metabolism of Staphylococcus aureus from an infected animal.

Gellenbeck, S. Mercy (Catholic University, Washington, D. C.). Aerobic respiratory metabolism of Staphylococcus aureus from an infected animal. J. Bacteriol. 83:450-455. 1962.-The separation of Staphylococcus aureus from the tissue fluids of an infected guinea pig has allowed a comparison of cells (GPR) separated in this manner with the same strain (PR847) grown on an artificial medium. In general, the respiratory response of organisms separated from tissue fluid was higher than that of staphylococci grown in vitro, though endogenous respiration of the in vitro strain consistently averaged 50% higher than the GPR cells. The guinea pig serum, defined medium, Trypticase soy broth, and the guinea pig filtrate were the complex substrates, listed in order of the least to the most stimulatory. Omission of nicotinamide and thiamine from the defined medium resulted in a decrease of oxygen consumption for the PR847 strain, but not for the GPR cells; however, when several amino acids were eliminated from the defined medium, the oxygen uptake of the GPR cells was depressed more than that of the staphylococci grown in vitro. In glucose alone, the organisms separated from the tissue fluid respired over 30% more effectively than the in vitro staphylococci. The filtrate, whether whole or boiled, provided a substrate in which organisms from both sources approximately doubled their oxygen uptake over that of either whole or boiled serum. Soluble components of the 50% ammonium sulfate fractionation of the filtrate stimulated GPR and PR847 cells more than did the 100% ammonium sulfate fraction under the conditions employed.

Amino Acids↗

PubMed1962

Endogenous respiration of Staphylococcus aureus.

Ramsey, H. H. (Stanford University, Palo Alto, Calif.). Endogenous respiration of Staphylococcus aureus. J. Bacteriol. 83:507-514. 1962.-The endogenous respiration of Staphylococcus aureus is dependent upon the medium used to grow the cell suspension. Within wide ranges, the concentration of glucose in the medium has no effect upon subsequent endogenous respiration of the cells, but the concentration of amino acids in the medium, within certain limits, has a very marked effect. The total carbohydrate content of the cells does not decrease during endogenous respiration. As endogenous respiration proceeds, ammonia appears in the supernatant, and the concentration of glutamic acid in the free amino acid pool decreases. Organisms grown in the presence of labeled glutamic acid liberate labeled CO(2) when allowed to respire without added substrate. The principal source of this CO(2) is the free glutamate in the metabolic pool; its liberation is not suppressed by exogenous glucose or glutamate. With totally labeled cells, the free pool undergoes a rapid, but not total, depletion and remains at a low level for a long time. Activity of the protein fraction declines with time and shows the largest net decrease of all fractions. Exogenous glucose does not inhibit the release of labeled CO(2) by totally labeled cells. Other amino acids in the free pool which can serve as endogenous substrates are aspartic acid and, to much lesser extents, glycine and alanine. The results indicate that both free amino acids and cellular protein may serve as endogenous substrates of S. aureus.

Alanine↗

PubMed1962

Isolation and partial characterization of a capsular material from Staphylococcus aureus.

Wiley, Bill B. (University of Saskatchewan, Saskatoon, Sask., Canada) and Jane C. Wonnacott. Isolation and partial characterization of a capsular material from Staphylococcus aureus. J. Bacteriol. 83:1169-1176. 1962.-An encapsulated strain of Staphylococcus aureus, which underwent a specific capsular reaction with homologous antiserum, was grown in a semisynthetic Casamino acids-glycerol broth. A fraction containing the capsular material was isolated from the culture supernatants. The preparation was antigenic in rabbits and absorbed the antibody responsible for both the passive protection of chick embryos and the specific capsular reaction in rabbit antiserum against the homologous organism. Chemically, the material was free of nucleic acids, contained 8% nitrogen, 4.25% total phosphorus, 26% hexosamine, and 26% reducing sugar. Acid hydrolysis yielded the amino acids glycine, alanine, glutamic acid, and lysine. Glucosamine and organic phosphate compounds were also present. Organic phosphate compounds were accounted for as glycerophosphate.

Acids↗

PubMed1962

Interrelationship of extracellular enzymes and pseudocapsulation in a strain of Staphylococcus aureus.

Sall, Theodore (University of Pennsylvania, Philadelphia, Pa.). Interrelationship of extracellular enzymes and pseudocapsulation in a strain of Staphylococcus aureus. J. Bacteriol. 83:1238-1243. 1962.-A pathogenic strain of Staphylococcus aureus, grown in the presence of a high concentration of lactose, mannitol, and gelatin, produces a great deal of soluble coagulase and a comparatively small amount of gelatinase. Owing to the nature of the growth conditions, the soluble coagulase may be prevented from diffusing into the medium. This results in the formation of a capsulelike structure, which has been termed "pseudocapsule." Presence of soluble coagulase about the cells in vivo might offer some protection to the staphylococci against the humoral and cellular defenses of the host.

Coagulase↗