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PubMed1961

Factors affecting filamentous growth of Sphaerotilus natans.

Filamentous growth in cultures of Sphaerotilus natans can be measured and compared with total growth by a standardized procedure of winding filaments around an inoculating needle. Filaments and residual growth are then separately washed on Millipore filters, dried, and weighed. This method has been used to study changes in the growth habit of S. natans elicited by changes in the concentration of nutrients in the medium. The concentration of peptone, in a medium containing a sugar, phosphate buffer, and inorganic salts, has a much greater effect on the proportion of filamentous growth than does the nature or concentration of the carbon source or the concentration of phosphate buffer. Filament formation is significantly inhibited by concentrations of peptone greater than 0.25%; further increases in peptone concentration stimulate the production of large amounts of capsular material. Increasing the concentration of phosphate buffer to 0.05 M almost completely inhibits growth of S. natans.

Sphaerotilus↗
PubMed2003

A novel gene encoding an enzyme that degrades a polysaccharide from the sheath of Sphaerotilus natans.

A gene encoding an enzyme that is able to depolymerize the basic polysaccharide prepared from the sheath of Sphaerotilus natans was identified in a sheath-degrading bacterium, Paenibacillus koleovorans. The gene was constructed from 2217 bp coding for 738 amino acids, including the signal sequence of 34 amino acids. No closely related protein or gene was indicated by a homology search. The gene was expressed in Escherichia coli as a glutathione S-transferase fusion protein. The fusion protein depolymerized the sheath polysaccharide into an oligosaccharide, introducing an unsaturated sugar residue, suggesting that the gene codes for a polysaccharide lyase acting on a basic polysaccharide.

Bacillus↗
PubMed1985

ATPase and cytochrome oxidase activities at the polar organelle in swarm cells of Sphaerotilus natans: an ultrastructural study.

The polar organelle of bacteria presumably is part of the flagellar apparatus. In order to characterize this structure, cytochemical studies on Sphaerotilus natans have been performed. Marked ATPase activity is associated with the inner boundary layer and central layer of this organelle. The spaces between the boundary layers and the central layer of the polar organelle which are traversed by fine fibrilles are positive for reactions with diaminobenzidine. This indicates cytochrome oxidase activity. S. natans possesses a ribbon-like, helically shaped polar organelle which is divided concomitantly with cell fission, possibly explaining inheritance of this structure and of the flagellar apparatus.

Adenosine Triphosphatases↗
PubMed1984

Growth rate of the bacterium Sphaerotilus natans in lead-containing medium and the effect of calcium ions.

Growth rate of bacteria Sphaerotilus natans in lead-containing medium (1 X 10(-4) M Pb2+) and bioaccumulation of lead in the bacterial cells were investigated together with the effect of calcium ions on these processes. A rapid increase in biomass was observed in the presence of calcium and lead whereas calcium alone had no visible effect on the bacterial growth. The increase in biomass in the presence of lead and calcium was accompanied by a pronounced drop in lead content in the bacterial cells. This suggests that calcium ions protect the bacterial cells against lead poisoning.

Cadmium↗
PubMed2003

Structure of the polysaccharide isolated from the sheath of Sphaerotilus natans.

A polysaccharide was isolated from the sheath of a sheathed bacterium, Sphaerotilus natans. The sheath polysaccharide (SPS) was composed of D-glucose and D-(N-acetyl)galactosamine in molar ratios of 1:4. Methylation linkage analysis revealed the presence of the residues of 4-linked glucose, 4-linked (N-acetyl)galactosamine, and 3-linked (N-acetyl)galactosamine in molar ratios of 1:3:1. The oligomer of SPS was prepared with an SPS-specific degrading enzyme from a sheath-degrading bacterium, Paenibacillus koleovorans. The oligomer was derivatized and subjected to fast atom bombardment-mass spectrometry to investigate the monosaccharide sequence of SPS. The structure of SPS was confirmed by nuclear magnetic resonance. The resulting data showed that SPS is a straight-chained basic polysaccharide constructed of a pentasaccharide repeating unit.

Acetylgalactosamine↗
PubMed2003

Metal speciation and pH effect on Pb, Cu, Zn and Cd biosorption onto Sphaerotilus natans: Langmuir-type empirical model.

Biosorption data of lead, copper, zinc and cadmium onto Sphaerotilus natans at different equilibrium pH (3-5 units) were here reported and analysed. Experimental results outlined the positive effect of pH increase on pollutant uptake and also the biomass affinity series (Pb > Cu > Zn > Cd) reflecting the hydrolytic properties of metals. An original empirical model was proposed to represent the effect of pH on heavy metal biosorption inserting q(max) vs. pH empirical functions into the classical Langmuir isotherm.

Adsorption↗
PubMed2002

Paenibacillus koleovorans sp. nov., able to grow on the sheath of Sphaerotilus natans.

Two bacterial strains that are able to grow specifically on the sheath of a sheathed filamentous bacterium, Sphaerotilus natans, were isolated from soil samples. The sheath-degrading organisms, designated strains TB(T) and TK, are facultatively anaerobic and form endospores. The Gram reaction was negative at all stages of cultivation. The optimum growth temperature and pH were 30 degrees C and pH 7. The DNA G+C content was 54.0-55.8 mol%. MK-7 was the predominant menaquinone and anteiso-C15:0 was the major fatty acid. Phylogenetic analysis based on the 16S rDNA sequences revealed that the isolates were closely related to Paenibacillus chondroitinus, Paenibacillus alginolyticus, Paenibacillus koreensis, Paenibacillus validus, Paenibacillus larvae subsp. larvae and P. larvae subsp. pulvifaciens. The sequences were found to contain consensus sequences characteristic of all Paenibacillus species. The isolates were able to lyse and utilize the purified sheath of S. natans as the sole carbon and energy source. Acid was not produced from common carbon sources, allowing easy distinction from other members of Paenibacillus. It is concluded that the two strains represent a novel Paenibacillus species, for which the name Paenibacillus koleovorans sp. nov. is proposed. The type strain is strain TB(T) (= JCM 11186T = IAM 14926T = KCTC 13912T).

Bacillus↗
PubMed1976

Determination of growth of Sphaerotilus discophorus in the presence of manganese.

Manganese interferes strongly with most chemical methods of biomass determination. However, the biomass of manganese-encrusted Sphaerotilus discophorus can be determined after removal of the MnO2 with trichloroacetic acid and oxalic acid. Evidence which indicates that manganese inhibits the heterotrophic growth of S. discophorus and that the cells only oxidize manganese late in the growth curve is presented.

Bacterial Proteins↗
PubMed1979

Isolation and characterization of a bacteriophage specific for Sphaerotilus natans which contain an unusual base in its deoxyribonucleic acid.

A bacteriophage was isolated specific for Sphaerotilus natans, an organism for which bacteriophages have not been previously described. This phage (designated SN1) was found to infect both the single-cell (S-type) and filamentous (R-type) forms of the host, although the sheath appeared to provide R-type cells with a degree of physical protection from infection. SN1 had a hexagonal head and a long flexible tail resembling most closely the phages in Bradley's group B. The nucleic acid was found to be deoxyribonucleic acid and contained an unusual base which substituted for 35% of the guanine. Deoxyribonucleic acid base composition was 56% cytosine plus guanine.

Adsorption↗
PubMed1979

Attached Growth of Sphaerotilus natans in Continuous-Flow Apparatus and Its Growth Inhibition by 9-beta-d-Arabinofuranosyladenine.

Sphaerotilus natans grew at the maximum specific growth rate (mu(max)) of 0.43/h when cultivated on PGY medium at 25 degrees C. The organism mainly grew attached to inside of the culture vessels when the culture medium was fed to the completely mixed continuous-flow apparatus at a dilution rate above mu(max) and the attached growth was directly related to the dilution rate. When a low concentration of the medium was supplied to the apparatus, almost all of the cells grown were filamentous and attached to the inside of the vessels. When a high concentration of the medium was fed, the organism grew as single cells or short chains and flowed out into the effluent. The attached growth of S. natans in the continuous-flow apparatus was inhibited by the minimal inhibitory concentration of 0.5 to 1.0 mug of 9-beta-d-arabinofuranosyladenine per ml. 9-beta-d-Arabinofuranosyladenine showed bacteriocidal activity against S. natans at a concentration of 50 to 100 mug/ml.

Journal Article↗
PubMed1980

New Selective Growth Inhibitors of Sphaerotilus natans, Anslimins A and B.

Selective growth inhibitors of Sphaerotilus natans were detected in the culture broths of several strains of Streptomyces. Anslimins A and B were isolated from the culture broth of Streptomyces oganonensis by adsorption on resinous adsorbent followed by elution with 50% aqueous acetone. The A and B components were then separated by cellulose powder chromatography. Physicochemical parameters of anslimins A and B revealed that these compounds are new peptide-containing structures. Anslimins A and B inhibited growth of S. natans at 0.78 and 0.39 mug/ml, respectively, but showed no activity against any of the other test microorganisms at 100 to 200 mg/ml. The anslimins had no harmful effect on guppies at a concentration of 100 mg/liter.

Journal Article↗
PubMed1980

Distribution of iron in sphaerotilus and the associated inhibition.

The distribution of iron between the sheaths and the cells of iron-inhibited Sphaerotilus cultures was determined. The experiment was conducted with different soluble iron forms as inhibitors. The growth inhibition was found to be related to the iron sorbed by the cells rather than by the sheaths. At the 90% inhibition level, iron sorbed by the cells ranged from 13 to 15 mg/g of organism for all three inhibitors tested. For 50% inhibition, the iron sorbed by the cells ranged from 7 to 8 mg/g of organism. The iron sorbed by the sheaths varied widely, ranging from 23 to 118 mg/g of organism at the 90% inhibition level and from 11 to 61 mg/g at the 50% inhibition level. The degree of inhibition is closely related to the amount of iron sorbed by the cells, which in turn is a function of the type of iron compound or complex used. The solubility of the iron is a major consideration.

Journal Article↗
PubMed1982

Growth of Sessile Sphaerotilus natans in a Tubular Recycle System.

The growth of sessile Sphaerotilus natans was measured in a continuous-flow recycle system. Four methods were used to confirm that the growth of the biofilm was a linear function that increased with time. Of the methods used, one monitored in situ biofouling (increased fluid frictional resistance), two indicated biomass (ATP and DNA per square centimeter), and one allowed the direct observation of replaceable test surfaces by scanning electron microscopy. The filamentous growth of S. natans caused an increase in the fluid frictional resistance. The increase in biofouling was directly proportional to the increase in biomass.

Journal Article↗
PubMed1988

Application of the Fluorescent-Antibody Technique for the Detection of Sphaerotilus natans in Activated Sludge.

Sphaerotilus natans, one of the most widely reported causes of bulking in activated sludge, can exist both within and outside of a sheath. It can easily be confused with similar activated sludge bacteria and thus can be overlooked when present in low numbers. Fluorescent antiserum was successfully prepared against the nonfilamentous form and was shown to be highly specific, showing no reaction with either pure cultures of similar filamentous bacteria or entirely unrelated organisms. It did, however, show a lack of strain specificity since it reacted with S. natans isolates from the Federal Republic of Germany and the United States and with filamentous bacteria in South African activated sludges. Fluorescent antibody is capable of penetrating the filaments of S. natans to stain the cells individually. The use of fluorescent antiserum in the identification of S. natans filaments obscured by activated sludge flocs and other suspended matter was simple since the cells stained brightly and could be observed through the less dense matter, while the use of other microscope techniques would be hampered by these obstructions. The use of fluorescent antibody will facilitate ecological studies of S. natans in activated sludge and other aqueous environments.

Journal Article↗
PubMed1998

Prevalence of broad-host-range lytic bacteriophages of Sphaerotilus natans, Escherichia coli, and Pseudomonas aeruginosa.

Two bacteriophage collections were examined with regard to their ability to form plaques on multiple bacterial host species. Nine of 10 phages studied were found to be broad-host-range bacteriophages. These phages fell into two groups. Group 1, the SN series, was isolated from sewage treatment plant samples with Sphaerotilus natans ATCC 13338 as a host. The DNAs of these bacteriophages contained modified bases and were insensitive to cleavage by type I and II restriction endonucleases. The efficiency of plating of these bacteriophages was changed only slightly on the alternate host. Group 2, the BHR series, was isolated by a two-host enrichment protocol. These bacteriophages were sensitive to restriction, and their efficiency of plating was dramatically reduced on the alternate host. Our results suggest that a multiple-host enrichment protocol may be more effective for the isolation of broad-host-range bacteriophages by avoiding the selection bias inherent in single-host methods. At least two of the broad-host-range bacteriophages mediated generalized transduction. We suggest that broad-host-range bacteriophages play a key role in phage ecology and gene transfer in nature.

Bacteriophages↗
PubMed2000

Purification and properties of an enzyme capable of degrading the sheath of Sphaerotilus natans.

Microorganisms which can degrade and grow on the purified sheath of a sheathed bacterium Sphaerotilus natans were collected from soil and river water. Two bacterial strains were isolated from the soil and designated strains TB and TK. Both strains are rod shaped, negatively stained by gram staining, facultatively anaerobic, and formed ellipsoidal endospores. These characteristics suggested that the isolates belong to the genus Paenibacillus, according to Ash et al. (C. Ash, F. G. Priest, and M. D. Collins, Antonie Leeuwenhoek 64:253-260, 1993). Phylogenetic analysis based on the 16S rDNA supported this possibility. Purification of the sheath-degrading enzyme was carried out from the culture broth of strain TB. The molecular weight of the enzyme was calculated to be 78,000 and 50, 000 by sodium dodecyl sulfate-polyacrylamide electrophoresis and gel filtration chromatography, respectively. Enzyme activity was optimized at pH 6.5 to 7.0 and 30 to 40 degrees C. The reaction was accelerated by the addition of Mg(2+), Ca(2+), Fe(3+), and iodoacetamide, whereas it was inhibited by the addition of Cu(2+), Mn(2+), and dithiothreitol. The enzyme acted on the polysaccharide moiety of the sheath, producing an oligosaccharide the size of which was between the sizes of maltopentaose and maltohexaose. As the reaction proceeded, the absorbance at 235 nm of the reaction mixture increased, suggesting the generation of unsaturated sugars. Incorporation of unsaturated sugars was also suggested by the thiobarbituric acid reaction. It is possible that the enzyme is not a hydrolytic enzyme but a kind of polysaccharide eliminase which acts on the basic polysaccharide.

Amino Acid Sequence↗
PubMed2002

Identification of a gene essential for sheathed structure formation in Sphaerotilus natans, a filamentous sheathed bacterium.

Sphaerotilus natans, a filamentous bacterium that causes bulking in activated sludge processes, can assume two distinct morphologies, depending on the substrate concentration for growth; in substrate-rich media it grows as single rod-shaped cells, whereas in substrate-limited media it grows as filaments. To identify genes responsible for sheath formation, we carried out transposon Tn5 mutagenesis. Of the approximately 20,000 mutants obtained, 7 did not form sheathed structures. Sequencing of the Tn5-flanking regions showed that five of the seven Tn5 insertions converged at the same open reading frame, designated sthA. The deduced amino acids encoded by sthA were found to be homologous to glycosyltransferase, which is known to be involved in linking sugars to lipid carriers during bacterial exopolysaccharide biosynthesis. Disruption of the gene of the wild-type strain by inserting a kanamycin resistance gene cassette also resulted in sheathless growth under either type of nutrient condition. These findings indicate that sthA is a crucial component responsible for sheath formation.

Bacterial Proteins↗