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PubMed1963

EFFECT OF PH AND AMMONIUM IONS ON THE PERMEABILITY OF BACILLUS PASTEURII.

Wiley, W. R. (Washington State University, Pullman), and J. L. Stokes. Effect of pH and ammonium ions on the permeability of Bacillus pasteurii. J. Bacteriol. 86:1152-1156. 1963.-Cell suspensions of Bacillus pasteurii require an alkaline pH (8.5 to 9.0) and NH(4) (+) for the oxidation of low concentrations (4 mum) of fumaric acid, glutamic acid, alanine, and other oxidizable substrates. In contrast, cells disrupted by a French press or by lysozyme oxidize these substrates at pH 7.2 and without NH(4) (+). Moreover, the alkaline pH and NH(4) (+) inhibit substrate oxidation by the broken cells. These striking differences between whole and disrupted cells suggest that pH and NH(4) (+) affect whole cells externally and not internally. It appears that the alkaline pH is needed to convert NH(4) (+) to free NH(3). The latter in turn is required by the cells for the transport of low concentrations of substrate across the cell membrane. At high concentrations (20 to 250 mum), substrates force entry into the cells by simple diffusion, thereby eliminating the need for a high pH and NH(4) (+) for oxidation.

Alanine↗
PubMed1963

HYDROLYSIS OF PROTEINS AND NUCLEIC ACIDS BY LANCEFIELD GROUP A AND OTHER STREPTOCOCCI.

Deibel, R. H. (American Meat Institute Foundation, Chicago, Ill.). Hydrolysis of proteins and nucleic acids by Lancefield group A and other streptococci. J. Bacteriol. 86:1270-1274. 1963.-Classically, group A streptococci have been considered to be nonproteolytic in spite of the observation that a proteinase is produced in broth cultures. When tested by the plate method, it was observed that 78% of 47 strains were proteolytic when the cultures were incubated anaerobically. Some strains hydrolyzed gelatin aerobically; however, the hydrolysis of casein and pepsin required anaerobic conditions of growth. Other proteins hydrolyzed included wheat gluten and a beef-muscle preparation. The hydrolysis of bovine serum albumin, lactalbumin, sheep plasma, and lysozyme was not detected in plate cultures. The hydrolysis of deoxyribonucleic acid and ribonucleic acid was characteristic of the majority of the strains. Unlike the proteolytic activity, the nucleolytic activity was independent of oxygen tension. Other streptococci were screened for hydrolytic activity; among these strains, only the single strain of Streptococcus sanguis tested possessed proteolytic activity. Deoxyribonuclease activity was observed in "animal" but not "human" group C strains, and in some strains of groups G and L.

Albumins↗
PubMed1964

METHICILLIN-INDUCED LYSOZYME-SENSITIVE FORMS OF STAPHYLOCOCCI.

Aldrich, K. M. (The University of Kansas, Lawrence), and C. P. Sword. Methicillin-induced lysozyme-sensitive forms of staphylococci. J. Bacteriol. 87:690-695. 1964.-Staphylococcus aureus and S. epidermidis grown in the presence of sublethal amounts of methicillin were converted to enlarged spheres within 2 to 4 hr, as shown by phase microscopy, Gram stain, and electron microscopy. Addition of lysozyme to cells incubated in the presence of methicillin, and to methicillin-induced spheres suspended in hypotonic saline, caused lysis of methicillin-treated cells but not of untreated cells.

Bacteriolysis↗
PubMed1964

FATE OF THE MESOSOMES OF BACILLUS MEGATERIUM DURING PROTOPLASTING.

Fitz-James, Philip (University of Western Ontario, London, Canada). Fate of the mesosomes of Bacillus megaterium during protoplasting. J. Bacteriol. 87:1483-1491. 1964.-When cells of Bacillus megaterium growing rapidly in peptone medium are treated with sucrose buffer prior to protoplasting, their membranous organelles or mesosomes are extruded as a collection of vesicles into the wall-membrane interspace. On subsequent protoplast formation with lysozyme digestion, the mesosome remnants become dispersed. If glucose is added to the peptone, a slightly more persistent mesosome can be seen and photographed by phase microscopy during lysozyme digestion, either as a wall-attached granule or as a protoplast tag. In thin section, mesosomes are found as small, variably dispersed aggregates of vesicles and wall-like material. Complete protoplasts are usually free from internal mesosomes but may contain twists or everted pockets of membrane on their periphery. By lysozyme digestion of partially fixed cells, the empty mesosome pockets in the membrane can be demonstrated in rod-shaped protoplasts.

Bacillus megaterium↗
PubMed1964

ELECTRON MICROSCOPE STUDY OF THE RELATIONSHIP BETWEEN MESOSOME LOSS AND THE STABLE L STATE (OR PROTOPLAST STATE) IN BACILLUS SUBTILIS.

Ryter, Antoinette (Institut Pasteur, Paris, France), and Otto E. Landman. An electron microscope study of the relationship between mesosome loss and the stable L-state (or protoplast state) in Bacillus subtilis. J. Bacteriol. 88:457-467. 1964.-In a prior publication, it was postulated that inability of protoplasts to restart cell-wall synthesis and cell division and the inability of stable mass-conversion L forms to return to the bacillary state were both equivalent and both due to the interruption of a membrane-associated reaction sequence. It was further postulated that this reaction sequence might reside in the mesosome. In the present publication, it is shown by means of electron microscopy of thin sections that protoplasts and L forms do not contain mesosomes. The sequence of events leading to loss of the mesosomes during protoplasting is as follows. Soon after lysozyme addition, the mesosomes are extruded from the cell interior into the space between cell wall and cytoplasmic membrane. Mesosome fragments in the form of small vesicles gather at the poles of the cells and are released, along with intact protoplasts, when the wall fragments. (Sudden shift of bacilli to hypertonic environment also causes extrusion and fragmentation of mesosomes, but this damage is later repaired.) In intact bacilli, mesosomes are in contact with both the peripheral membrane and nuclear material. Upon extrusion of the mesosomes, a direct attachment between nuclear material and cytoplasmic membrane is observed. Deoxyribonucleic acid (DNA)-membrane attachment may play a role in the control of DNA replication. Bacillus subtilis L-colonies consist of irregularly shaped bodies of varying sizes, bounded only by a membrane. Many of the smaller bodies do not contain nuclear material, and many of the large ones appear inviable. Division is accomplished by a disorganized-appearing constriction process. There are no septa.

Bacillus↗
PubMed1964

PROPERTIES OF A LYSOZYME-DISSOCIATED ENDOTOXIC FRACTION FROM ESCHERICHIA COLI.

Mergenhagen, Stephan E. (National Institute of Dental Research, Bethesda, Md.), and George R. Martin. Properties of a lysozyme-dissociated endotoxic fraction from Escherichia coli. J. Bacteriol. 88:1169-1174. 1964.-Treatment of a phenol-water preparation of C(14)-labeled Escherichia coli O91-H21 endotoxin of low solubility with lysozyme at pH 5.0 or 8.0 effected a dissociation of the preparation. Such products of dissociation were equally distributed in the chloroform and water phases after extraction. beta-Glucosidase, but not beta-galactosidase, significantly dissociated this endotoxin also. Concomitant with dissociation, recoverable endotoxin after lysozyme treatment had a reduced content of bound lipid, and dissolved easily in aqueous media to yield a clear solution. Examination of lysozyme-treated endotoxin in an analytical ultracentrifuge revealed that it sedimented as a single major boundary with a sedimentation coefficient of 13.3. Lysozyme-treated endotoxin was more potent than was the conventional endotoxin as evidenced by lethal activity in rabbits and pertussis-sensitized mice. Agar-gel diffusion analysis indicated that the higher molecular weight component associated with conventional endotoxin was dissociated by lysozyme treatment. In immunoelectrophoresis, lysozyme-treated endotoxin was observed as a single sharp band of precipitation which migrated toward the cathode.

Animals↗
PubMed1964

RESISTANT PROPERTIES OF AZOTOBACTER CYSTS INDUCED IN RESPONSE TO MINERAL DEFICIENCIES.

Layne, Joseph S. (University of Mississippi School of Medicine, Jackson), and Emmett J. Johnson. Resistant properties of Azotobacter cysts induced in response to mineral deficiencies. J. Bacteriol. 88:956-959. 1964.-Cysts produced in response to mineral deficiencies, and apparently lacking the characteristic exine and intine, possess the same degree of resistance to heat, mechanical disruption, desiccation, the action of lysozyme, and the combined action of ethylenediaminetetraacetic acid (EDTA) and lysozyme as do butanol-induced cysts. Slight differences in the behavior of the two varieties of cysts toward EDTA were observed. Since no significant differences seem to exist in resistant properties between cysts induced in response to mineral deficiencies and n-butanol-induced cysts, it would seem that the current concepts attributing the resistant properties of the Azotobacter cyst to the exine and intine require modification.

Azotobacter↗
PubMed1965

SOLUBILIZATION OF THE CONJUGATION INHIBITOR FROM ESCHERICHIA COLI CELL WALL.

Schwartz, Gabriel H. (National Institute of Arthritis and Metabolic Diseases, Bethesda, Md.), Donald Eiler, and Milton Kern. Solubilization of the conjugation inhibitor from Escherichia coli cell wall. J. Bacteriol. 89:89-94. 1965.-Conjugation between F(-) and HfrC strains of Escherichia coli is inhibited by the presence of cell wall derived from either strain. The inhibitor can be solubilized from such cell walls or whole cells by treatment with periodate. The soluble material is relatively acid-labile and alkali-stable, nondialyzable, nonsedimentable at 100,000 x g (1 hr), partially sedimented after 3 hr at 100,000 x g, sensitive to small changes in ionic strength, neutralized by cationic reagents, and is insensitive to proteinases, nucleases, lipases, and carbohydrases. The soluble inhibitor derived from male and female cells is indistinguishable by all the criteria tested.

Antimetabolites↗
PubMed1965

EFFECT OF ENZYMES ON THE INTERACTION OF ENTEROVIRUSES WITH LIVING HELA CELLS.

Zajac, Ihor (Hahnemann Medical College, Philadelphia, Pa.), and Richard L. Crowell. Effect of enzymes on the interaction of enteroviruses with living HeLa cells. J. Bacteriol. 89:574-582. 1965.-Eight crude enzyme preparations and two crystalline enzymes were tested for ability to inactivate coxsackie group B and poliovirus receptors on living HeLa cells. Receptor-destroying enzyme, erepsin, lysozyme, collagenase, proteinase, and cobra venom did not alter attachment of coxsackie B3 or poliovirus T1 to cells, whereas elastase prevented attachment of both viruses tested. Treatment of live cells with pancreatin or chymotrypsin rendered cells unable to attach group B coxsackie viruses, whereas cells treated with trypsin failed to attach poliovirus T1. In addition, chymotrypsin was found to release coxsackie B3 and poliovirus T1 from cell surfaces, whereas trypsin was unable to dissociate virus-cell union. These results indicate that cellular receptors for polioviruses differ from those for group B coxsackie-viruses. The finding that 1% solutions of enzymes will inactivate differentially the enteroviral receptors of HeLa cells, without altering cell viability, provides a useful approach for study of enterovirus receptors of live host cells.

Animals↗
PubMed1965

ELECTRON MICROSCOPE OBSERVATIONS ON INTACT CELLS, PROTOPLASTS, AND THE CYTOPLASMIC MEMBRANE OF BACILLUS STEAROTHERMOPHILUS.

Abram, Dinah (Purdue University, Lafayette, Ind.). Electron microscope observations on intact cells, protoplasts, and the cytoplasmic membrane of Bacillus stearothermophilus. J. Bacteriol. 89:855-873. 1965.-Negatively stained preparations of protoplasts and fragments of cytoplasmic membranes from cells of Bacillus stearothermophilus ruptured by treatment with sonic oscillation, partial lysis with lysozyme, autolysis, or phage infection were examined electron microscopically. Specimens of intact cells also were examined by the same technique. The following structural details were revealed. Intact or nearly intact, partially swollen, elongated protoplasts and their ghosts have a characteristic differentiated surface texture and can easily be distinguished from the cell wall. Infoldings of the cytoplasmic membrane can be observed in these protoplasts, to which flagella are attached; the latter originate via hooks from "basal structures" that are in close association with the cytoplasmic membrane or part of it. Abundant intracytoplasmic membranous elements, which appear to be tubular or vesicular, can be seen in whole cells of three of the strains studied. The fine structure of the cytoplasmic membrane and probably that of its intracytoplasmic infoldings was observed on flattened and folded membrane fragments, one layer thick. Structural units, roughly spherical, 65 to 85 A in diameter, were present on one side of the cytoplasmic membrane, facing the cytoplasm. They were attached loosely to the membrane by fine stalks, 40 to 60 A long, and were easily detached, probably leaving the stalks behind them on the membrane. While the greater stability of membranes from thermophiles made this study of the fine structure possible, the structural units described were demonstrated also on cytoplasmic membranes from mesophiles.

Bacillus↗
PubMed1965

FORMATION OF SPHEROPLASTS FROM BACILLUS ANTHRACIS.

Chatterjee, B. R. (Baylor University College of Medicine, Houston, Tex.), and Robert P. Williams. Formation of spheroplasts from Bacillus anthracis. J. Bacteriol. 89:1128-1133. 1965.-Spheroplasts were prepared from Bacillus anthracis by combined treatment with lysozyme and glycine. Glycine, at a final concentration of 3%, was added to cultures of B. anthracis in nutrient broth that had grown at 37 C for 16 to 18 hr under 50% CO(2). After additional incubation under CO(2) for 2 hr, lysozyme, at the appropriate concentration (50 to 100 mug/ml), and sucrose, to a concentration of 15%, were added, and incubation was continued for 2 to 6 hr in CO(2). At the end of this period, incubation in CO(2) was discontinued. Spheroplasts formed after incubation in air for 6 to 12 hr. Lysozyme alone exhibited the same effect when added at much higher concentrations (500 to 2,000 mug/ml) to cultures growing under CO(2). No spheroplasts formed when cultures were treated with glycine alone. Treatment with lysozyme was more effective on smooth strains than rough. Cells from young cultures were more susceptible to lysozyme than older cells. CO(2) apparently was essential for formation of spheroplasts from B. anthracis.

Bacillus anthracis↗
PubMed1965

LYSIS OF BACTERIAL PROTOPLASTS AND SPHEROPLASTS BY STAPHYLOCOCCAL ALPHA-TOXIN AND STREPTOLYSIN S.

Bernheimer, Alan W. (New York University School of Medicine, New York, N.Y.), and Lois L. Schwartz. Lysis of bacterial protoplasts and spheroplasts by staphylococcal alpha-toxin and streptolysin S. J. Bacteriol. 89:1387-1392. 1965.-Protoplasts of Bacillus megaterium, Sarcina lutea, and Streptococcus pyogenes, and spheroplasts of Escherichia coli were lysed by staphylococcal alpha-toxin, whereas spheroplasts of Vibrio metschnikovii and V. comma were not. In the spectrum of its lytic action, streptolysin S qualitatively resembled staphylococcal alpha-toxin except for failure to lyse S. pyogenes protoplasts. In contrast to the two foregoing agents, streptolysin O did not lyse protoplasts and spheroplasts. The observations are interpreted in relation to similarities and differences in lipid composition of bacterial and mammalian cell membranes.

Animals↗
PubMed1965

BINDING OF RIBOSOMES TO CYTOPLASMIC RETICULUM OF BACILLUS MEGATERIUM.

Schlessinger, David (Washington University School of Medicine, St. Louis, Mo.), Vincent T. Marchesi, and Benjamin C. K. Kwan. Binding of ribosomes to cytoplasmic reticulum of Bacillus megaterium. J. Bacteriol. 90:456-466. 1965.-As many as 60% of the cellular ribosomes are bound to membrane "ghosts" in lysozyme lysates in 0.02 m Mg(2+). Bound ribosomes labeled with C(14)-uracil do not exchange with added unlabeled ribosomes, even after disruption of the cell membrane by sonic treatment. Electron micrographs of thin sections of ghosts, or of fragments produced by sonic disruption of protoplasts, indicate that the ribosomes are distributed on a reticular matrix which extends throughout the cytoplasm. The binding of ribosomes to this matrix is insensitive to ribonuclease or deoxyribonuclease, and has many other features in common with the binding of ribonucleoprotein to the membranous elements of the mammalian microsomal fraction, though the reticulum does not appear to be membranous. Thus, functioning ribosomes may be bound to a cytoplasmic structure in all cell types.

Bacillus megaterium↗