Erwinia Species Research Articles

Comparative Gel-Electrophoresis Studies of Ribosomal Proteins of Erwinia Species and Members of the Enterobacteriaceae

Comparative Gel-Electrophoresis Studies of Ribosomal Proteins of Erwinia Species and Members of the Enterobacteriaceae

Factors governing pectate lyase synthesis in soft rot and non-soft rot bacteria

Regulation of pectate lyase synthesis was examined in Erwinia and Pseudomonas species. Soft rot bacteria produced 100- to 1000-fold more enzyme per cell under optimal conditions than did other bacterial pathogens or saprophytes. Among pseudomonads, only Pseudomonas marginalis and a few other fluorescent strains isolated from plant tissue synthesized pectate lyase. Constitutive synthesis was common in this group. In contrast, lyase synthesis in most Erwinia species examined was inducible. Polypectate and pectin were effective carbon sources for lyase induction in some Erwinia strains while other strains showed much higher inducible synthesis on pectin than on polypectate. Vegetable extracts had profound effects on lyase synthesis. Potato extract, which was previously reported as exerting a synergistic effect on induction of pectate lyase in Erwinia carotovora ATCC 8061 grown on pectin, repressed lyase synthesis in other Erwinia strains. At high concentrations, extracts of carrot, lettuce and onion severely repressed constitutive and inducible synthesis. At low concentrations, lettuce and onion extracts stimulated constitutive lyase synthesis in Pseudomonas marginalis. The wide variety of regulatory controls governing lyase synthesis and the repressive as well as synergistic effects of vegetable extracts on synthesis suggest that the etiology of bacterial soft rot diseases can be influenced by such regulatory mechanisms.

Asparaginase and glutaminase activities of bacteria.

SUMMARY: A test-tube method is described for the determinations of L-asparaginase and L-glutaminase in suspensions and extracts of bacteria. An automated modification of the method was used to determine the asparaginase activities of about 200 strains from 78 species and the glutaminase activities of 46 strains from 13 species. Both enzymes were widely distributed and, at pH 8.5, asparaginase was generally the more active. Asparaginase was exceptionally active in some species of Erwinia.

Glucose fermentation endproducts of Erwinia spp. and other enterobacteria.

Summary.The endproducts formed by Erwinia spp. and other enterobacteria from the anaerobic fermentation of glucose were determined by thin‐layer chromatography and other micromethods. The 71 strains examined fell into 15 mixed acid fermentation end‐product patterns of the sort which are considered to be characteristic of the Enterobacteriaceae. The patterns ranged from the detectable formation by 6 strains of all 7 of the products which were determined (carbon dioxide, succinate, lactate, formate, acetate, 2,3‐butanediol, and ethanol) to the detectable formation by one strain of only two (carbon dioxide and lactate); 32 strains formed 6 of the products; 21 strains formed 5 of the products; 9 strains formed 4 of the products; two strains formed 3 of the products. Each of the named species (nomenspecies) of the genus Erwinia does not, in general, have a characteristic pattern of fermentation endproducts; the nonphytopathogenic enterobacteria share many of the patterns shown by Erwinia spp.

Unusual Fermentative, Gram-Negative Bacilli Isolated from Clinical Specimens

Five strains of gram-negative, yellow chromogenic bacilli were recovered from clinical specimens which fit the characteristics of the "lathyri-herbicola group" within the genus Erwinia. The strains were facultatively anaerobic, fermentative, anaerogenic bacilli with peritrichous flagella which grew at 37 C, reduced nitrate to nitrite, and failed to produce oxidase, pectinase, arginine dihydrolase, and decarboxylases for lysine and ornithine. Aggregations of bacteria (symplasmata) were observed in the syneresis water of slant cultures, and analogous granular aggregates and biconvex, spindle-shaped bodies developed in colonies on plate cultures. Awareness of these characteristics should result in more frequent identification of Erwinia species from human sources.

DNA base composition and taxonomy of phyopathogenic and other enterobacteria.

SUMMARY Using lysates and purified DNA, base ratios were determined by the buoyant density ultracentrifugation and the absorbance-temperature transition techniques ; the correspondence was very high between the two methods. The DNAs from a large number of Erwinia species, mostly phytopathogenic and nonphytopathogenic, but including some ‘Erwinia-like’ bacteria from animal sources and from other genera of the family Enterobacteriaceae were studied. The DNA base ratios of these bacteria fell mainly in the range 50–58 % GC, consistent with their taxonomic placement in the family Enterobacteriaceae. Certain assemblages of erwinias could be grouped on the basis of GC content into clearly differentiated clusters, which, accidentally or otherwise, correlated neatly with certain existing nomenclatural groupings. It was not possible, from the GC values alone, to decide whether the present multiplicity of Erwinia species can be justified as separate species, or whether and how they might be combined into fewer species, or whether and how they might be demoted to some infraspecific level. Indeed, it is not clear whether the genus Erwinia, defined as it is solely on the basis of plant habitat, should be maintained or whether its species might not, just as rationally, be distributed throughout other genera of the family Enterobacteriaceae. Classifications of the genus Erwinia on over-all phenotypic similarity result in a small number of specific taxa which, on the basis of the present study, are seen to contain organisms of different GC contents. In the present state of the art, one can only be agnostic about the amount of such differences in GC content which corresponds to separate taxa or to a particular categoreal level (generic, specific, infraspecific) in the present hierarchical taxonomic scheme.

Cell division in a species of Erwinia. XII. A study of nutritional influences in D-serine inhibition of growth and division of Erwinia sp., and of certain specific sites of D-serine action.

D-Serine-induced inhibitions of growth and cell division of Erwinia sp. are greatly influenced by the pH and composition of the medium. In a glucose-aspartic medium, optimum elongation occurs at pH 6.8–7.2. In an aspartic acid medium, glucose, independently of pH, enhances division inhibition, but reduces growth inhibition. In ammonia media, a high toxicity is generally accompanied by poor inhibition of division. Division inhibition in ammonia media increases with decreasing ammonia concentration, and with increasing pantothenate concentration. Growth inhibition and division inhibition can, to a large extent, be varied independently of one another. Because of the nutritional dependence of division inhibition, it is proposed that the primary mechanism controlling the rate of division with respect to the rate of growth, and hence cell length, is at the metabolic level.D-Serine causes a marked accumulation of keto acids in most ammonia media as well as in a glucose – aspartic acid medium. This accumulation, decreased by added pantothenate, is the result of inhibition of pantothenate synthesis. D-Serine inhibits the entry of aspartic acid into the cell; this is a major factor in D-serine inhibition of growth. Filaments grown in the presence of D-serine show no decrease relative to normal cells in content of DNA, RNA, or protein.

Cell division in a species of Erwinia. XI. Some aspects of the carbon and nitrogen nutrition of Erwinia species.

The species of Erwinia used in cell division studies (Grula 1960a) will grow on L- or D-aspartic acid, but no other amino acid, as a sole source of carbon, nitrogen, and energy. Ammonia is utilizable as a sole source of nitrogen; in this case the rate and extent of growth are significantly influenced by the carbon source. Of all compounds tested, malic acid supports the most rapid and abundant growth in an ammonium chloride – mineral salts medium. Added pantothenate often stimulates growth in ammonium chloride media, but not in aspartic acid media. Growth in an ammonium chloride – glucose – salts medium is rather slow and limited. Marked stimulation occurs by supplementation with intermediates of the Krebs cycle, even though the compound supports little or no growth as a sole carbon source. Neither L-glutamic acid nor α-ketoglutaric acid supports growth as a sole carbon source; this is believed to result from impermeability of the cell to these compounds.

Cell division in a species of Erwinia. X. Morphology of the nuclear body in filaments produced by growth in the presence of D-serine.

Filamentous cells of Erwinia sp. produced by growth in the presence of D-serine possess nuclear bodies that are not dividing normally. The nuclear bodies can be highly convoluted and continuous throughout large portions of the filaments. Possible reasons for failure of the nuclear body to periodically divide and suggested relationships to division of the cell are discussed.

A human infection caused by an Erwinia species

A case is reported describing the repetitive isolation of an Erwinia species from an infected area of skin over the medial malleolus of a fractured ankle. The likely environmental source of this organism was the stockinette wrap used under the plaster cast. Bacteriologic and immunologic aspects of the organisms involved are described. It is suggested that opportunistic human infection by members of the genus Erwinia may be encountered more readily than previously envisaged.

Effects of certain penicillins on growth and cell division in a species of Erwinia.

SUMMARY: By using growth and division-inhibition at 16 hr as indices of activity, eight penicillins, differing in the side chain, were tested against an Erwinia species, and compared with benzylpenicillin. DL-α-Aminobenzylpenicillin, DL-3-chloro-α-aminobenzylpenicillin, D-α-aminobenzylpenicillin, and methicillin were more toxic for growth than was benzylpenicillin. 6-Aminopenicillanic acid and cloxacillin were about equal to benzylpenicillin in toxicity; triphenylmethylpenicillin and 2-ethoxy-1-naphthylpenicillin were much less toxic. All the compounds inhibited division of the bacteria but, at 50% of normal growth, methicillin, cloxacillin and 2-ethoxy-1-naphthylpenicillin resulted in significantly longer organisms than the others. Pantoyl lactone, when present in the medium from the time of inoculation, in all cases decreased the length of the organisms, increased growth (with a highly toxic concentration of penicillin), and decreased the accumulation of keto acids and ultraviolet-absorbing materials in the medium. It was concluded that the side chain of these penicillins is not essential for the inhibition of growth and division of this Erwinia sp.; quantitative differences in activity associated with the side chain appear to result from the influence of the side chain on factors such as penetration, or strength of binding at the active site.

Cell division in a species of Erwinia. IX. Electron microscopy of normally dividing cells.

Grula, E. A. (Oklahoma State University, Stillwater), and Gerald L. Smith. Cell division in a species of Erwinia. IX. Electron microscopy of normally dividing cells. J. Bacteriol. 90:1054-1058. 1965.-Cells of an Erwinia species (an Enterobacteriaceae) divide by concomitant invagination of the cell wall and membrane. It is concluded that the process is initiated and sustained by the cell membrane.

ACTION OF CYCLOSERINE ON A SPECIES OF ERWINIA WITH REFERENCE TO CELL DIVISION.

D-Cycloserine not only strongly inhibited growth of an Erwinia species, but, at levels allowing some growth, inhibited cell division. The resulting long cells often showed thickening or swelling. Several agents were able to prevent this effect. D-Alanine, at a level that overcame growth inhibition completely, still allowed considerable elongation to take place. To overcome division inhibition completely required an approximately 300-fold higher concentration than that completely overcoming growth inhibition under the conditions used. Similar results were obtained with L-alanine, but at a given concentration it was less effective than D-alanine. Pantoyl lactone partially overcame growth inhibition, and, at higher levels which reduced growth, completely overcame division inhibition. Pyridoxal overcame growth inhibition to a large extent, but increased elongation and damage to cells. Pantoyl lactone and L-alanine showed a high degree of synergism in overcoming both growth and division inhibition by D-cycloserine. Pantoyl lactone plus D-alanine, or pyridoxal plus either D- or L-alanine also showed such a synergism, but to a lesser extent. The significance of these findings with regard to known enzyme inhibitions of D-cycloserine is discussed.

BACTERIA RESPONSIBLE FOR MUCILAGE-LAYER DECOMPOSITION IN KONA COFFEE CHERRIES.

The predominant microbial flora present during decomposition of the mucilage layer of Kona coffee cherries were gram-negative bacteria which fermented lactose rapidly. Cultures isolated from coffee cherries under-going fermentation included species of Erwinia, Paracolobactrum, and Escherichia. Unblemished cherry surfaces and coffee plantation soil also had a microflora containing a high proportion of bacteria belonging to these three genera. Of 168 isolates tested, the 44 strains capable of demucilaging depulped coffee cherries were all members of Erwinia dissolvens. Supernatant growth medium liquids, after removal of E. dissolvens cells, actively decomposed the mucilage layer of depulped cherries.

Bacteria Responsible for Mucilage-Layer Decomposition in Kona Coffee Cherries1

The predominant microbial flora present during decomposition of the mucilage layer of Kona coffee cherries were gram-negative bacteria which fermented lactose rapidly. Cultures isolated from coffee cherries under-going fermentation included species of Erwinia, Paracolobactrum, and Escherichia. Unblemished cherry surfaces and coffee plantation soil also had a microflora containing a high proportion of bacteria belonging to these three genera. Of 168 isolates tested, the 44 strains capable of demucilaging depulped coffee cherries were all members of Erwinia dissolvens. Supernatant growth medium liquids, after removal of E. dissolvens cells, actively decomposed the mucilage layer of depulped cherries.

Cell division in a species of Erwinia. VII. Amino sugar content of dividing and nondividing cells

Several agents which inhibit cell division affect cell wall synthesis. Tuttle & Gest (1960) reported that several D-amino acids increased cell wall content of amino sugars in Rhodospirillum rubrum . Vancomycin, penicillin, and 5-fluorouracil, all of which inhibit cell division in a species of Erwinia , ( Grula & Grula, 1962) cause a reduction in cell wall mucopeptide in gram-positive and gram-negative bacteria ( Rogers and Perkins, 1960; Tomasz and Borek, 1962; Reynolds, 1962; Lederberg, 1957; Strominger, Park, and Thompson, 1959; Wylie and Johnson, 1962; Roberts and Johnson, 1962; Collins and Richmond, 1962). Aim of this study was to determine cell wall content of glucosamine (GA) and muramic acid (MA) of Erwinia cells grown under a wide variety of division inhibiting and reversing conditions and thus to determine if an alteration in amino sugar content or a change in the GA MA ratio was associated with cell elongation.

A taxonomic study of Erwinia amylovora (Burrill 1882) Winslow et al. 1920

SUMMARY In the present report we give the results of our studies of the morphological, cultural, and biochemical properties of 49 strains of Erwinia amylovora. On the basis of our results, we propose a new description of this species. The following tests are most suitable for the differentiation of E. amylo-vora from other species of the genus Erwinia: pectinase, lactose, and the reduction of nitrates. We recommend that the strain BS 1114 (NCPPB 683) be considered a neotype.

Characteristics of Erwinia‐like Organisms found in Plant Material

SummaryThe characters of 20 nonpigmented and 2 yellow pigmented isolates of Ervinia‐like organisms from plant material (primarily pome fruit) are described and compared with those of Erwinia amylovora. Cultures of some other Erwinia species were also included in the study for comparison. It is suggested, on the basis of their similarity to Erw. amylovora, that they should be included in the genus Erwinia, although they have no obvious pathogenic role. The relationship of these organisms with Erw. lathyri and Bacterium herbicola is discussed.

Reversal of mitomycin c-induced growth and division inhibition in a species of Erwinia.

MITOMYCIN c, an anti-tumour agent from culture filtrates of Streptomyces caespitosus, is effective against both Gram-positive and negative bacteria, and is bacteriocidal to growing and non-growing bacteria1. It is an extremely potent inhibitor of growth and cell division of an Erwinia species, using a synthetic medium2 normally supporting excellent growth.

Cell division in a species of Erwinia. V. Effect of metabolic inhibitors on terminal division and composition of a "division" medium.

Grula, E. A. (Oklahoma State University, Stillwater) and Mary M. Grula. Cell division in a species of Eriwinia. V. Effect of metabolic inhibitors on terminal division and composition of a "division" medium. J. Bacteriol. 84:492-499. 1962.-Terminal division in Erwinia spp. involves a triggering action and subsequent septum synthesis. It is a metabolic process requiring organic nitrogen and carbon and energy. The process, when triggered by pantoic acid or pantoyl lactone, is inhibited strongly by 2,4-dinitrophenol, hydroxylamine, mitomycin C, and Hg ion and to a lesser degree by cyanide, azide, 5-fluorouracil, and diisopropylfluorophosphate. Ethylenediaminetetraacetic acid completely inhibits division only when calcium ion is the triggering agent. Heating of the cells at 43 C for 10 to 20 min also completely inhibits division. Hydroxylamine, iodoacetate, and mitomycin C cause extensive lysis of growing cells. No evidence has been obtained to demonstrate the need for protein or normal ribonucleic acid synthesis in terminal division. Requirement for intact deoxyribonucleic acid (DNA) or DNA synthesis is questionable; -SH groups are not directly involved. Once triggering has occurred, septum formation appears to require synthesis of at least cell-wall mucopeptide. A "division" medium is reported and discussed.