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M Kageyama

Publications and source records attributed to M Kageyama.

At least 91 records · Page 5Linked to original sources

Genetic determinant of pyocin R2 in Pseudomonas aeruginosa PAO. I. Localization of the pyocin R2 gene cluster between the trpCD and trpE genes.

Thirty-seven mutants defective in pyocin R2 production in the P. aeruginosa PAO strain were subjected to fine mapping of pyocin R2 genes by transduction with phage F116L. Sixteen complementation groups (designated prtA through prtP) involved in pyocin R2 production were tentatively identified by complementation tests using phage F116L. Their linkages to trpC and trpE markers and fine mapping by three point crosses demonstrated that most of the mutations (prtA through prtN) were located in between trpC and trpE, and that the prtP mutation was localized outside this major prt cluster but in the proximity of the rifA and strA region.

Bacteriocins↗

Genetic determinant of pyocin R2 in Pseudomonas aeruginosa PAO. II. Physical characterization of pyocin R2 genes using R-prime plasmids constructed from R68.45.

The chromosome segment which contains the genes responsible for production of pyocin R2 in P. aeruginosa PAO was defined physically using R-prime plasmids constructed in vivo from R68.45. The previous conclusion from genetic mapping that the cluster of pyocin R2 genes is located in between trpC and trpE genes was confirmed by deletion mapping of various R prime plasmids bearing the trpC gene. The pyocin R2 gene cluster was further localized on two contiguous HindIII fragments of 16 kb and 8.0 kb. PML14 strain, in which R-type pyocin genes were completely deleted, had only one 11 kb HindIII fragment instead. Heteroduplexes between this 11 kb fragment with the two HindIII fragments of PAO revealed that the cluster of pyocin R2 genes was an insertion 13 kb long.

Bacteriocins↗

Isolation and characterization of a new bacteriophage, KF1, immunologically cross-reactive with F-type pyocins.

Pseudomonas aeruginosa strain NIH S produced a bacteriophage, KF1, immunologically cross-reactive with F-type pyocins. Phage KF1 was neutralized by both anti-pyocin F1 and anti-pyocin F3 sera, although the efficiency was very low. About eleven polypeptides were detected by SDS-polyacrylamide gel electrophoresis of the phage. Most of the subunit proteins were different from those of F-type pyocins, but the molecular weights of minor subunit proteins P3 and P6 seemed to be the same as those of band 1 and band 5 of F-type pyocins, respectively. The head of the phage appeared to have an icosahedral structure, approximately 63 nm in diameter, with a long (190 nm, 11 nm wide and about 45 striations) flexuous tail connected to a fiber structure (about 53 nm in length). The density in CsCl and the sedimentation coefficient of the phage were 1.54 g/ml and 392S, respectively. Some other biochemical properties were described. The nucleic acid of the phage was linear, double stranded DNA of molecular weight 4 x 10(7). The density of the DNA in CsCl was 1.719 g/ml, the melting temperature was 95.4 degrees C. The guanine plus cytosine content was calculated to be 60 to 64%.

Bacteriocins↗

The effect of defocusing on the electron microscopic image of the extended particle of pyocin R1.

The effect of defocusing on the electron microscopic image of the extended particle of pyocin R1 was examined with the aid of optical diffraction. The results show that the through-focus image of the cross-striated particle changed to a fishbone-like image with a little under-focusing, which had been considered to be a transitional state during the sheath contraction of phage G. In the optical diffraction pattern of the defocused image, a strong meridional reflection corresponding to the distance of cross-striations in the through-focus image almost disappeared, supporting the change to the fishbone-like image on defocusing.

Bacteriocins↗

Genetic mapping of bra genes affecting branched-chain amino acid transport in Pseudomonas aeruginosa.

Pseudomonas aeruginosa PAO mutants defective in the transport systems for branched-chain amino acids were isolated and characterized. Two mutations in strains selected for trifluoroleucine resistance, braA300 and braB307, were mapped in the met-9020-dcu-9108 and the nar-9011-puuC10 region, respectively. The mutation loci in strains selected for azaleucine resistance, braC310 and bra-311 through bra-314, were all located near the fla genes, with an order of region I fla-bra-region II fla. Strains with braA300 showed a marked reduction in the high-affinity branched-chain amino acid transport system (LIV-I) and a considerable decrease in the lower-affinity system (LIV-II). Strains with braB307 were found to be defective in the LIV-II system. Strains selected for azaleucine resistance were all defective only in the LIV-I system and fell into three phenotypically distinct classes. Strains with braC310 produced a binding protein for leucine, isoleucine, valine, alanine, and threonine (LIVAT-BP) altered in binding ability, indicating that the braC gene is the structural one for the LIVAT-BP. Strains with bra-311 or bra-312 showed a complete loss of production of the LIVAT-BP. Strains with bra-313 or bra-314 produced normal levels of functional LIVAT-BP, suggesting that these mutations are located in a gene(s) other than braC.

Amino Acids, Branched-Chain↗

Ultrastructural visualization of complex carbohydrates in epiphyseal cartilage with the tannic acid-metal salt methods.

The present study has ultrastructurally applied the tannic acid-ferric chloride (TA-Fe) and the TA-uranyl acetate (TA-UA) methods to thin sections of glutaraldehyde-fixed, unosmicated embedded epiphyseal cartilage from rat tibiae to demonstrate complex carbohydrates. The strongest TA-Fe and TA-UA staining was observed after fixation of the specimens in glutaraldehyde containing TA. TA-Fe (pH 1.5) strongly stained matrix granules presumed to be proteoglycan monomers and chondrocyte secretory granules at various maturational stages but did not stain collagen fibrils and glycogen. TA-UA (pH 4.2) strongly stained matrix granules, intracellular glycogen, and chondrocyte secretory granules, and moderately stained collagen fibrils in the cartilage matrix. Ribosomes and nuclei were not stained above background staining with UA alone. In alpha-amylase-digested specimens, all TA-UA-reactive cytoplasmic glycogen was selectively removed. Testicular hyaluronidase digestion of specimens selectively removed TA-UA staining in matrix granules and all TA-Fe staining. When the pH of the UA solution was reduced to 1.5, TA-UA staining of glycogen and collagen was markedly decreased or absent, whereas staining of anionic sites was unaltered and significantly greater than with UA staining alone. Thus the TA-metal salt methods are pH dependent and allow differential intracellular and extracellular localization of complex carbohydrates in cartilage tissues at the electron microscope level.

Animals↗

The peptidoglycan-associated lipoprotein (PAL) of the Proteus mirabilis outer membrane: characterization of the peptidoglycan-associated region of PAL.

The peptidoglycan-associated lipoprotein (PAL) is present in the cell envelope in a form closely, but not covalently, associated with peptidoglycan in various Gram-negative bacteria. When the cell envelope or the isolated peptidoglycan-PAL complex from Proteus mirabilis, in which PAL maintains the interaction with peptidoglycan, was digested with trypsin, a polypeptide fragment with molecular weight 11,000 (11 K fragment) was obtained. However, when isolated PAL or the 11 K-fragment which had been dissociated from peptidoglycan was treated with trypsin, they were further digested. The 11 K-fragment maintained essentially the same tight interaction with peptidoglycan as intact PAL. These results indicate that the 11 K-fragment is probably derived from the peptidoglycan-associated region of the PAL molecule. The purified 11 K-fragment contained neither covalently-linked fatty acid nor glycerylcysteine, which are known to be present at the N-terminus of PAL. The N-terminal sequence of the 11 K-fragment was also determined.

Amino Acid Sequence↗

Mutational separation of transport systems for branched-chain amino acids in Pseudomonas aeruginosa.

Several types of Pseudomonas aeruginosa mutants defective in the transport systems for branched-chain amino acids were isolated by selection for resistance to 5',5',5'-DL-trifluoroleucine, a leucine analog, under certain conditions. Mutants resistant to trifluoroleucine in the absence of Na+ were defective in the high-affinity system. These mutants fell into two classes. One class showed a defect in the production of a periplasmic binding protein for leucine, isoleucine, valine, alanine, and threonine, and the other showed normal production of the binding protein as determined by a binding assay and by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Properties of the former class of mutants have been partly described (T. Hoshino and M. Kageyama, J. Bacteriol. 141:1055-1063, 1980). Mutants selected for resistance to trifluoroleucine with Na+ and an excess amount of alanine showed a defect in the low-affinity system. Membrane vesicles prepared from such a mutant lost the transport activity for leucine. A mutant which showed increased activity of the low-affinity system with a defect in the high-affinity system was obtained from strain PML1453 (high-affinity system defective) by selecting for utilization of isoleucine as a carbon source.

Alanine↗

Comparative study of F-type pyocins of Pseudomonas aeruginosa.

Pseudomonas aeruginosa strain PAF41 was found to produce a new F-type pyocin, pyocin F3, the action spectrum of which was different from those of previously reported pyocins F1 and F2. These three F-type pyocins were compared with respect to their structure and biological properties. These pyocins were almost the same with regard to the structure and the dimensions, and have similar amino acid compositions and S values. The particle weights of these pyocins were also suggested to be similar. Analyses of subunit proteins by SDS-polyacrylamide slab gel electrophoresis showed that these pyocins were composed of 5 major (bands 1, 2, 3, 4, and 6) and 2 minor (bands 5 and 7) subunit proteins and that no difference in the mobilities of these subunit proteins could be detected among the pyocins except that of the second major subunit protein (band 4), which did differ. Pyocins F1, F2, and F3 were immunologically cross-reactive, and carried common antigens as well as specific ones. It was shown that band 6 was a common antigen among the three pyocins and that band 4 was antigenically different in pyocins F1 and F3 by immunological reaction after protein blotting. Electron microscopic observation of pyocin particles treated with anti-sera revealed that the common antigens were located on the rod part and the specific ones were on the fiber part. Pyocin F3 was neutralized by both anti-F3 and anti-F1 sera showing apparent first order rate kinetics, whereas the neutralization for pyocin F1 by these sera did not show such kinetics, but a considerable increment of pyocin F1 activity was observed when small amounts of the sera were added. The increment seemed to be due to the antibodies common to pyocins F1, F2, and F3. A phage, which had a flexuous rod-like tail, was found to be immunologically cross-reactive with the three pyocins and was named KF1.

Amino Acids↗

Purification and properties of an S-type pyocin, pyocin AP41.

Pyocin AP41, a protease-sensitive bacteriocin produced by Pseudomonas aeruginosa PAF41, was purified to a homogeneous state and characterized. The molecular weight of this pyocin was about 95,000 as determined by the combination of gel filtration and sedimentation velocity analysis. This pyocin was a complex of two kinds of polypeptides. Highly purified preparations showed two protein bands on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and their apparent molecular weights were 90,000 and 6,000 to 7,000, respectively. Two proteins could be separated by gel filtration in the presence of 6 M urea. Amino acid compositions of these components were determined. The large component had pyocin activity similar to the complex, whereas the small component did not. Sensitive cells were killed by this pyocin only under growing conditions and with single-hit kinetics. The pyocin-treated cells lysed in about 30 min with concomitant production of their resident pyocins or phages. The induced production of resident pyocins caused by pyocin AP41 depended on a recA gene function.

Amino Acids↗

Effect of iron concentration in the growth medium on the sensitivity of Pseudomonas aeruginosa to pyocin S2.

The iron concentration in the growth medium was found to affect the susceptibility of Pseudomonas aeruginosa PML1550 to pyocin S2, a bacteriocin. The efficiency of killing by pyocin S2 was very low when the indicator cells were grown in an iron-rich medium. The capacity of these cells to adsorb pyocin S2 was reduced. Cultivation under limitation of iron (1 microM or less) was necessary to produce a fully sensitive cell population. The growth under iron limitation was accompanied by the appearance of four protein components in the outer membrane of the cells. Nine mutants resistant to pyocin S2 were isolated and their outer membranes were analyzed. They all lacked one component (Fe-b protein) as well as the adsorption capacity for pyocin S2. These findings suggest a possible role of this protein as the receptor for pyocin S2.

Bacteriocins↗

Purification and properties of a binding protein for branched-chain amino acids in Pseudomonas aeruginosa.

A binding protein for branched-chain amino acids was purified to a homogeneous state from shock fluid of Pseudomonas aeruginosa PML14. It was a monomeric protein with an apparent molecular weight of 4.3 x 10(4) or 4.0 x 10(4) by sodium dodecyl sulfate-polyacrylamide gel electrophoresis or gel filtration, respectively. The isoelectric point was determined to be pH 4.1 by electrofocusing. Amino acid analysis of the protein showed that aspartic acid, glutamic acid, glycine, and alanine were major components and that the protein contained only one residue each of tryptophan and cysteine per molecule. The binding protein contained no sugar. The binding activity of the protein was specific for the branched-chain amino acids. The protein also bound alanine and threonine with lower affinity. The dissociation constants of this protein for leucine, isoleucine, and valine were found to be 0.4, 0.3, and 0.5 microM, respectively. Mutants defective in the production of the binding protein were identified among the mutants deficient in a transport system for branched-chain amino acids (LIV-I). The revertants from these mutants to LIV-I-positive phenotype simultaneously recovered normal levels of the binding protein. These findings suggest strongly the association of the binding protein with the LIV-I transport system.

Bacterial Proteins↗

Comparative study on R-type pyocins of Pseudomonas aeruginosa.

Four R-type pyocins (R1, R2, R3, and R4) produced by different Pseudomonas aeruginosa strains were compared with respect to their structure and action methanism. It is known that these bacteriocins have structures similar to contractile bacteriophage tails and serologically cross-react with each other, but they are distinguished according to difference in range of sensitive strains. All these pyocins were shown to arrest the synthesis of protein and nucleic acid in sensitive cells, as previously reported for pyocin R1. Action of pyocin R3 was shown to require calcium ion. Although antiserum prepared against one pyocin neutralized other R-type pyocins as well as the homologous pyocin, some differences in antigen specificity were found between pyocin R1 and pyocin R2 and R3 antibody blocking assays. Electron microscopic observation of pyocin particles treated with the antiserum pre-absorbed with heterologous pyocin revealed that specific antigens were located on the distal portion of the fibers. Comparison of protein composition showed these pyocins to be composed of essentially similar subunit proteins but a subunit protein supposed to be a main constituent of the fiber was different in its molecular weight among these pyocins. These results suggest that the main structural difference of these pyocins is to be found in the fiber.

Bacteriocins↗