Properties and characteristics of a bacteriocin-like substance produced by Propionibacterium acnes isolated from dental plaque

1988 ◽  
Vol 34 (12) ◽  
pp. 1344-1347 ◽  
Author(s):  
Greg E. Paul ◽  
S. James Booth
Keyword(s):  
Molecular Weight ◽  
Ionic Strength ◽  
Dental Plaque ◽  
Propionibacterium Acnes ◽  
Gram Positive ◽  
Gram Negative ◽  
A Cell ◽  
Approximate Molecular Weight ◽  
Low Ionic Strength

A cell-associated bacteriocinlike substance with an approximate molecular weight of 78 000 was isolated from an oral isolate of Propionibacterium acnes. The substance was bacteriostatic and was active against both gram-positive and gram-negative anaerobes. Lysozyme inhibited the activity of the bacteriocinlike substance at low ionic strength.

Antithrombin III Binding to Surface Immobilized Heparin and Its Relation to F Xa Inhibition

1987 ◽  
Vol 58 (04) ◽  
pp. 1064-1067 ◽  
Author(s):  
K Kodama ◽  
B Pasche ◽  
P Olsson ◽  
J Swedenborg ◽  
L Adolfsson ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Ionic Strength ◽  
Surface Coating ◽  
Antithrombin Iii ◽  
Lower Class ◽  
Biologically Active ◽  
High Affinity ◽  
Heparin Coating ◽  
Continuous Surface ◽  
Approximate Molecular Weight

SummaryThe mode of F Xa inhibition was investigated on a thromboresistant surface with end-point attached partially depoly-merized heparin of an approximate molecular weight of 8000. Affinity chromatography revealed that one fourth of the heparin used in surface coating had high affinity for antithrombin III (AT). The heparin surface adsorbed AT from both human plasma and solutions of purified AT. By increasing the ionic strength in the AT solution the existence of high and low affinity sites could be shown. The uptake of AT was measured and the density of available high and low affinity sites was found to be in the range of 5 HTid 11 pic.omoles/cmf, respectively Thus the estimated density of biologically active high and low ailmity heparm respectively would be 40 and 90 ng/cm2 The heparin coating did not take up or exert F Xa inhibition by itself. With AT adsorbed on both high and low affinity heparin the surface had the capacity to inhibit several consecutive aliquots of F Xa exposed to the surface. When mainly high affinity sites were saturated with AT the inhibition capacity was considerably lower. Tt was demonstrated that the density of AT on both high and low affinity heparin determines the F Xa inhibition capacity whereas the amount of AT on high affinity sites limits the rate of the reaction. This implies that during the inhibition of F Xa there is a continuous surface-diffusion of AT from sites of a lower class to the high affinity sites where the F Xa/AT complex is formed and leaves the surface. The ability of the immobilized heparin to catalyze inhibition of F Xa is likely to be an important component for the thromboresistant properties of a heparin coating with non-compromized AT binding sequences.

scholarly journals Degradation of Polycyclic Aromatic Hydrocarbons by Moderately Halophilic Bacteria from Luzon Salt Beds

2018 ◽  
Vol 8 (19) ◽  
Author(s):  
Carolyn L. Nanca ◽  
Kimberly D. Neri ◽  
Anna Christina R. Ngo ◽  
Reuel M. Bennett ◽  
Gina R. Dedeles
Keyword(s):  
Molecular Weight ◽  
Polycyclic Aromatic Hydrocarbons ◽  
Aromatic Hydrocarbons ◽  
Halophilic Bacteria ◽  
Sole Source ◽  
The Philippines ◽  
Liquid Fuels ◽  
Gram Positive ◽  
Gram Negative ◽  
Polycyclic Aromatic

Background. Polycyclic aromatic hydrocarbons (PAHs) are common environmental contaminants which are highly toxic due to their carcinogenic and mutagenic effects. They are released into the environment by incomplete combustion of solid and liquid fuels, accidental spillage of oils and seepage from industrial activities. One of the promising processes mitigating PAHs is through biodegradation. However, conventional microbiological treatment processes do not function well at high salt concentrations. Hence, utilization of halophilic bacteria should be considered. Objectives. This study aimed to assess the ability of halophilic bacteria isolated from local salt beds in Pangasinan and Cavite, the Philippines, to degrade PAHs pyrene, fluorene and fluoranthene. Methods. Polycyclic aromatic hydrocarbon-tolerant halophilic bacteria collected from two sampling sites were phenotypically characterized, molecularly identified and tested to determine their potential to degrade the PAHs pyrene, fluorene and fluoranthene at a hypersaline condition. Best PAH degraders were then assayed to identify the optimal degradation using such parameters as pH, temperature and PAH concentration. Testing for enzyme degradation was also done to determine their baseline information. Extraction and analysis of degraded PAHs were performed using centrifugation and UV-vis spectrophotometry. Results. Twelve isolates from both collection sites tolerated and grew in culture with selected PAHs. These were identified into four genera (Halobacillus, Halomonas, Chromohalobacter, and Pontibacillus). Selected best isolates in a series of biodegradation assays with the above-mentioned parameters were Halobacillus B (Collection of Microbial Strains (CMS) 1802) (=trueperi) (Gram-positive) for pyrene and fluoranthene, and Halomonas A (CMS 1901) (Gram-negative) for fluorene. Degrader biomass and PAH degradation were invariably negatively correlated. Qualitative tests with and without peptone as a nitrogen source implied enzymatic degradation. Discussion. Polycyclic aromatic hydrocarbons utilized by these halophilic bacteria served as a sole source of carbon and energy. Implications of biodegradation of the two best isolates show that high molecular weight (HMW) (4-ring) pyrene tends to be degraded better by Gram-positive bacteria and low molecular weight (3-ring) fluorene by Gram-negative degraders. Conclusions. Halophilic bacteria constitute an untapped natural resource for biotechnology in the Philippines. The present study demonstrated their potential use in bioremediation of recalcitrant hydrocarbons in the environment. Competing Interests. The authors declare no competing financial interests.

scholarly journals Protein diffusion through charged nanopores with different radii at low ionic strength

2014 ◽  
Vol 16 (39) ◽  
pp. 21570-21576 ◽  
Author(s):  
Pieter Stroeve ◽  
Masoud Rahman ◽  
Lekkala Dev Naidu ◽  
Gilbert Chu ◽  
Morteza Mahmoudi ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Ionic Strength ◽  
Protein Diffusion ◽  
Similar Molecular Weight ◽  
Low Ionic Strength ◽  
Charged Membranes ◽  
Pore Permeability

Pore permeability for two similar molecular weight proteins (BSA and BHb) through nanoporous charged membranes at low ionic strength (I = 0.001 M).

Human and Bovine Plasminogen-Free Thrombin, Purified by Means of Gel Filtration and Ion Exchange Chromatography

1966 ◽  
Vol 15 (03/04) ◽  
pp. 501-510 ◽  
Author(s):  
W Berg ◽  
K Korsan-Bengtsen ◽  
J Ygge
Keyword(s):  
Molecular Weight ◽  
Ionic Strength ◽  
Large Scale ◽  
Gel Filtration ◽  
Trisodium Citrate ◽  
Exchange Chromatography ◽  
Simple Method ◽  
Commercial Preparation ◽  
Usual Manner ◽  
Low Ionic Strength

SummaryA simple method for preparation of plasminogen-free human and bovine thrombin is described.Crude thrombin was prepared in the usual manner from oxalated plasma by means of adsorption on BaSO4, elution with trisodium citrate and activating the eluate from BaSO4 with tissue thromboplastin.This crude thrombin was purified by means of gel-filtration and chromatography on CM-Sephadex A-50.The gel-filtration was performed on three types of Sephadex, G-75, G-50, and G--25. By means of Sephadex G-75 the thrombin was well separated from the main part of inert protein and this type of Sephadex was used for the purification in large-scale. Separation of thrombin from protein of higher molecular weight was also obtained with Sephadex G-50 but not with Sephadex G-25 indicating a molecular weight of thrombin between 4000 and 10,000.The importance of using an elution buffer of sufficient high ionic strength for gel-filtration is shown. A great deal of the thrombin was adsorbed to the Sephadex if the gel-filtration was performed at a too low ionic strength.The final preparation contained 30,000 NIH units of thrombin per mg tyrosin and no detectable plasminogen.The commercial preparation “Topostasine” was also purified in the same manner, but the plasminogen content in “Topostasine” was high and could not be completely separated from thrombin.

scholarly journals Production and characterisation of a marine Halomonas surface-active exopolymer

2019 ◽  
Vol 104 (3) ◽  
pp. 1063-1076
Author(s):  
Tony Gutierrez ◽  
Gordon Morris ◽  
Dave Ellis ◽  
Barbara Mulloy ◽  
Michael D. Aitken
Keyword(s):  
Molecular Weight ◽  
Ionic Strength ◽  
High Molecular Weight ◽  
Positive Influence ◽  
Contaminated Sites ◽  
Crude Oils ◽  
Magnetic Resonance Spectroscopic Analysis ◽  
Surface Active ◽  
Low Ionic Strength ◽  
Pure Hydrocarbon

AbstractDuring screening for novel emulsifiers and surfactants, a marine gammaproteobacterium, Halomonas sp. MCTG39a, was isolated and selected for its production of an extracellular emulsifying agent, P39a. This polymer was produced by the new isolate during growth in a modified Zobell’s 2216 medium amended with 1% glucose, and was extractable by cold ethanol precipitation. Chemical, chromatographic and nuclear magnetic resonance spectroscopic analysis confirmed P39a to be a high-molecular-weight (~ 261,000 g/mol) glycoprotein composed of carbohydrate (17.2%) and protein (36.4%). The polymer exhibited high emulsifying activities against a range of oil substrates that included straight-chain aliphatics, mono- and alkyl- aromatics and cycloparaffins. In general, higher emulsification values were measured under low (0.1 M PBS) compared to high (synthetic seawater) ionic strength conditions, indicating that low ionic strength is more favourable for emulsification by the P39a polymer. However, as observed with other bacterial emulsifying agents, the polymer emulsified some aromatic hydrocarbon species, as well as refined and crude oils, more effectively under high ionic strength conditions, which we posit could be due to steric adsorption to these substrates as may be conferred by the protein fraction of the polymer. Furthermore, the polymer effected a positive influence on the degradation of phenanthrene by other marine bacteria, such as the specialist PAH-degrader Polycyclovorans algicola. Collectively, based on the ability of this Halomonas high-molecular-weight glycoprotein to emulsify a range of pure hydrocarbon species, as well as refined and crude oils, it shows promise for the bioremediation of contaminated sites.

Activity of Telithromycin (HMR 3647) against Anaerobic Bacteria Compared to Those of Eight Other Agents by Time-Kill Methodology

1999 ◽  
Vol 43 (8) ◽  
pp. 2027-2031 ◽  
Author(s):  
Kim L. Credito ◽  
Lois M. Ednie ◽  
Michael R. Jacobs ◽  
Peter C. Appelbaum
Keyword(s):  
Propionibacterium Acnes ◽  
Anaerobic Bacteria ◽  
Bacteroides Fragilis ◽  
Bacteroides Thetaiotaomicron ◽  
Gram Positive ◽  
Gram Negative ◽  
Amoxicillin Clavulanate ◽  
Erythromycin A ◽  
Time Kill ◽  
Kinetics Of

ABSTRACT Time-kill studies examined the activities of telithromycin (HMR 3647), erythromycin A, azithromycin, clarithromycin, roxithromycin, clindamycin, pristinamycin, amoxicillin-clavulanate, and metronidazole against 11 gram-positive and gram-negative anaerobic bacteria. Time-kill studies were carried out with the addition of Oxyrase in order to prevent the introduction of CO2. Macrolide-azalide-ketolide MICs were 0.004 to 32.0 μg/ml. Of the latter group, telithromycin had the lowest MICs, especially against non-Bacteroides fragilis group strains, followed by azithromycin, clarithromycin, erythromycin A, and roxithromycin. Clindamycin was active (MIC ≤ 2.0 μg/ml) against all anaerobes except Peptostreptococcus magnus and Bacteroides thetaiotaomicron, while pristinamycin MICs were 0.06 to 4.0 μg/ml. Amoxicillin-clavulanate had MICs of ≤1.0 μg/ml, while metronidazole was active (MICs, 0.03 to 2.0 μg/ml) against all exceptPropionibacterium acnes. After 48 h at twice the MIC, telithromycin was bactericidal (≥99.9% killing) against 6 strains, with 99% killing of 9 strains and 90% killing of 10 strains. After 24 h at twice the MIC, 90, 99, and 99.9% killing of nine, six, and three strains, respectively, occurred. Lower rates of killing were seen at earlier times. Similar kill kinetics relative to the MIC were seen with other macrolides. After 48 h at the MIC, clindamycin was bactericidal against 8 strains, with 99 and 90% killing of 9 and 10 strains, respectively. After 24 h, 90% killing of 10 strains occurred at the MIC. The kinetics of clindamycin were similar to those of pristinamycin. After 48 h at the MIC, amoxicillin-clavulanate showed 99.9% killing of seven strains, with 99% killing of eight strains and 90% killing of nine strains. At four times the MIC, metronidazole was bactericidal against 8 of 10 strains tested after 48 h and against all 10 strains after 24 h; after 12 h, 99% killing of all 10 strains occurred.

Effect of acclimating saccharides on the activated sludge bacterial population: composition abnormality of activated sludge acclimated to glucose

1998 ◽  
Vol 37 (4-5) ◽  
pp. 99-103
Author(s):  
Yuu Ubukata ◽  
Susumu Takii
Keyword(s):  
Molecular Weight ◽  
Chemical Composition ◽  
Activated Sludge ◽  
Bacterial Population ◽  
Municipal Sewage ◽  
Appreciable Amount ◽  
Low Molecular Weight ◽  
Population Composition ◽  
Gram Positive ◽  
Gram Negative

The question of whether the substitution of glucose for starch in municipal sewage as an acclimating saccharide for activated sludge (AS) in the laboratory is valid was investigated using activated sludges acclimated to glucose (G-AS) and dextrin (D-AS), since the bacteria responsible for starch (dextrin) removal in D-AS are verified to take up maltose instead of glucose during dextrin removal. In G-AS, polysaccharides are the major reserve materials, and large amounts of residual organic materials (ROM) are excreted from the AS. In contrast, in D-AS, about half of the reserve materials are low molecular weight saccharides, and no appreciable amount of ROM was detected. It is considered that most bacteria responsible for the removal of dextrin and glucose are Gram-negative and Gram-positive, respectively, based on the results of the chemical composition of AS and the type of reserve saccharide. As a result, in laboratory-scale AS processes, maltose (disaccharide) or dextrin (polysaccharide), instead of glucose (monosaccharide), should be used as a substitute for starch.

Comparative Microbiological and Immunological Studies of Subgingival Dental Plaque from Man and Baboons

1990 ◽  
Vol 69 (1) ◽  
pp. 55-59 ◽  
Author(s):  
K.T. McMahon ◽  
M.O. Wasfy ◽  
W.P. Yonushonis ◽  
G.E. Minah ◽  
W.A. Falkler
Keyword(s):  
Animal Models ◽  
Dental Plaque ◽  
Bacterial Population ◽  
Oral Diseases ◽  
Papio Anubis ◽  
Gram Positive ◽  
Oral Flora ◽  
Gram Negative ◽  
The Mean

Baboons may be useful as animal models for the study of human oral diseases and infections. They are closely related to man anatomically, physiologically, and phylogenetically. Plaque and gingival indices were relatively low in 18 baboons (Papio anubis). The mean scores ranged between 0.62 ± 0.29 and 0.37 ± 0.20, respectively. Gram-positive and Gram-negative cocci comprised 27.0 ± 32.4 and 3.1 ± 7.5% of the total viable counts in the dental plaque samples. Black-pigmented Bacteroides formed about 1.9 ± 5.9% of the bacterial population in the samples. Anaerobic Gram-negative bacilli were found in 73.2% of the samples and averaged 19.2 t 26.3% of the total recovered flora. Species of the oral Actinomyces and other Gram-positive rods found in humans were not isolated. The composition of the oral flora in baboons appeared to be significantly different from that of man. Isolates of F. nucleatum, L. buccalis, and B. intermedius from the two mammals were biochemically similar, but were distinguishable by analysis with antibody, both by precipitin lines and/or differences between homologous and heterologous titers.

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