scholarly journals Bacterial Oxidation of Dibromomethane and Methyl Bromide in Natural Waters and Enrichment Cultures

1998 ◽  
Vol 64 (12) ◽  
pp. 4629-4636 ◽  
Author(s):  
K. D. Goodwin ◽  
J. K. Schaefer ◽  
R. S. Oremland
Keyword(s):  
Carbon Source ◽  
Methane Oxidation ◽  
Methyl Bromide ◽  
Half Life ◽  
Sole Carbon Source ◽  
Natural Waters ◽  
The Other ◽  
Bacterial Oxidation ◽  
Enrichment Cultures ◽  
Saline Waters

ABSTRACT Bacterial oxidation of14CH2Br2 and14CH3Br was measured in freshwater, estuarine, seawater, and hypersaline-alkaline samples. In general, bacteria from the various sites oxidized similar amounts of14CH2Br2 and comparatively less 14CH3Br. Bacterial oxidation of14CH3Br was rapid in freshwater samples compared to bacterial oxidation of 14CH3Br in more saline waters. Freshwater was also the only site in which methyl fluoride-sensitive bacteria (e.g., methanotrophs or nitrifiers) governed brominated methane oxidation. Half-life calculations indicated that bacterial oxidation of CH2Br2 was potentially significant in all of the waters tested. In contrast, only in freshwater was bacterial oxidation of CH3Br as fast as chemical removal. The values calculated for more saline sites suggested that bacterial oxidation of CH3Br was relatively slow compared to chemical and physical loss mechanisms. However, enrichment cultures demonstrated that bacteria in seawater can rapidly oxidize brominated methanes. Two distinct cultures of nonmethanotrophic methylotrophs were recovered; one of these cultures was able to utilize CH2Br2 as a sole carbon source, and the other was able to utilize CH3Br as a sole carbon source.

Lag, adaptation and ageing in a micro-organism ( Bact. lactis aerogenes )

1961 ◽  
Vol 155 (959) ◽  
pp. 195-201 ◽  
Keyword(s):  
Carbon Source ◽  
Generation Time ◽  
Sole Carbon Source ◽  
The Other ◽  
Lag Phase ◽  
Glucose Medium ◽  
Galactosidase Activity ◽  
Aerobacter Aerogenes ◽  
Isomerase Activity

The lag preceding growth of Bact. lactis aerogenes (Aerobacter aerogenes) after a first transfer to a medium containing D-arabinose as sole carbon source increases with the age and decreases with the size of the inoculum. During the long lag phase the β -galactosidase activity declines steeply. In contrast with this (and with a control ageing in a glucose medium) the D-ribulose isomerase activity is maintained, although no detectable consumption of D-arabinose occurs. If the long lag of unadapted cells in D-arabinose is divided into parts by intermediate passages in glucose or lactose media, the sum of the partial lags is nearly constant and equal to that observed when there is no interruption. But the periodic passages in the other media increase the rate at which growth eventually occurs in the D-arabinose. It is concluded that during the lag a decay of the enzymes in general occurs concomitantly with the development of the specific mechanisms concerned in the utilization of the new substrate. The balance of these processes (together with varying loss or retention of diffusible metabolites) is largely responsible for the observed variations in lag and mean generation time.

Selective medium for the isolation and enumeration of Mycobacterium avium-intracellulare and M. scrofulaceum

1986 ◽  
Vol 32 (1) ◽  
pp. 10-14 ◽  
Author(s):  
Karen L. George ◽  
Joseph O. Falkinham III
Keyword(s):  
Carbon Source ◽  
Mycobacterium Avium ◽  
Sole Carbon Source ◽  
Natural Waters ◽  
Tween 80 ◽  
Selective Medium ◽  
Selective Isolation ◽  
Mineral Salts ◽  
Mycobacterium Avium Intracellulare

A medium for the selective isolation and enumeration of Mycobacterium avium-intracellulare and M. scrofulaceum (MAIS) was developed, based upon the ability of these mycobacteria to utilize Tween 80 as sole carbon source and grow optimally at pH 5.5 on a simple mineral salts medium. Representative MAIS strains had higher efficiencies of plating on the Tween 80 medium compared with Middlebrook 7H10. It was shown that nonmycobacterial organisms in natural waters had lower efficiencies of plating on the Tween 80 medium and smaller colonies, thus allowing direct isolation and enumeration of the slowly growing mycobacteria without overgrowth.

Evidence against the involvement of adenosine 3′,5′-cyclic monophosphate in glucose inhibition of β-galactosidase induction in Bacillus megaterium

1976 ◽  
Vol 54 (10) ◽  
pp. 854-865 ◽  
Author(s):  
Kwok-Him Yeung ◽  
Gillian Chaloner-Larssgn ◽  
Hiroshi Yamazaki
Keyword(s):  
Escherichia Coli ◽  
Carbon Source ◽  
Bacillus Megaterium ◽  
Sole Carbon Source ◽  
The Other ◽  
Cyclic Monophosphate ◽  
Glucose Inhibition ◽  
Significant Rate ◽  
Phosphorylated Compounds ◽  
Grown Culture

When Bacillus megaterium cells are grown on D-galactose as the sole carbon source, the cells actively synthesize β-galactosidase (β-D-galactoside galactohydroIase, EC 3.2.1.23). However, D-galactose, when added to a glucose-grown culture, did not induce β-galactosidase, apparently because of the glucose inhibition of the transport of galactose. On the other hand, when glucose was added to a galactose-grown culture, the transport of galactose continued at a reduced but significant rate, whereas further synthesis of β-galactosidase was halted. Adenosine 3′,5′-cyclic monophosphate (cAMP) or guanosine 3′,5′-cyclic monophosphate (cGMP) did not relieve the glucose inhibition of β-galactosidase synthesis in the preinduced culture. A method which gave a reproducible assay of c[32P]AMP in Escherichia coli did not detect cAMP or cGMP in a B. megaterium culture undergoing β-galactosidase induction, but revealed the extracellular accumulation of two unknown phosphorylated compounds. Cell-free extracts prepared from galactose-grown cells did not catalyze the degradation of cAMP or cGMP.

scholarly journals Engineering of Cyclodextrin Glucanotransferase on the Cell Surface of Saccharomyces cerevisiae for Improved Cyclodextrin Production

2006 ◽  
Vol 72 (3) ◽  
pp. 1873-1877 ◽  
Author(s):  
Zhankun Wang ◽  
Qingsheng Qi ◽  
Peng George Wang
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Carbon Source ◽  
Sole Carbon Source ◽  
Immunofluorescence Microscopy ◽  
Coupling Reaction ◽  
The Other ◽  
Yeast Fermentation ◽  
Cyclodextrin Glucanotransferase ◽  
Regulated Expression ◽  
Cyclodextrin Production

ABSTRACT The cyclodextrin glucanotransferase (CGTase) gene (cgt) from Bacillus circulans 251 was cloned into plasmid pYD1, which allowed regulated expression, secretion, and detection. The expression of CGTase with a-agglutinin at the N-terminal end on the extracellular surface of Saccharomyces cerevisiae was confirmed by immunofluorescence microscopy. This surface-anchored CGTase gave the yeast the ability to directly utilize starch as a sole carbon source and the ability to produce the anticipated products, cyclodextrins, as well as glucose and maltose. The resulting glucose and maltose, which are efficient acceptors in the CGTase coupling reaction, could be consumed by yeast fermentation and thus facilitated cyclodextrin production. On the other hand, ethanol produced by the yeast may form a complex with cyclodextrin and shift the equilibrium in favor of cyclodextrin production. The yeast with immobilized CGTase produced 24.07 mg/ml cyclodextrins when it was incubated in yeast medium supplemented with 4% starch.

Bacterial Degradation of 2-Methylisoborneol

1988 ◽  
Vol 20 (8-9) ◽  
pp. 205-210 ◽  
Author(s):  
G. Izaguirre ◽  
R. L. Wolfe ◽  
E. G. Means
Keyword(s):  
Drinking Water ◽  
Water Treatment ◽  
Carbon Source ◽  
Lake Water ◽  
Sole Carbon Source ◽  
Natural Waters ◽  
Bacterial Degradation ◽  
Sediment Samples ◽  
Water And Sediment ◽  
Water And Sediment Samples

2-Methylisoborneol (MIB) is a musty-odored compound occurring in natural waters that is difficult to remove by conventional water treatment methods. Biodegra-dation may be an alternative for its removal from drinking water. Studies were undertaken to determine the conditions enhancing MIB degradation and to isolate and identify the bacteria responsible. MIB degraders were enriched using mg/l levels of the compound, in a defined mineral medium, inoculated with water and sediment samples from reservoirs where MIB is seasonally produced. Cultures that degraded MIB were isolated and enumerated. Degradation occurred only in mixed cultures. MIB supported growth as sole carbon source at 1-6.7 mg/l. MIB at 10 µg/l was also degraded in sterile lake water inoculated with washed bacteria. The degradation of MIB at both µg/l and mg/l levels took from 7 days to more than 2 weeks.

Influence of electron donors and copper concentration on geochemical and mineralogical processes under conditions of biological sulphate reduction

2014 ◽  
Vol 64 (1) ◽  
pp. 138-146
Author(s):  
Dorota Wolicka ◽  
Andrzej Borkowski
Keyword(s):  
Carbon Source ◽  
Sole Carbon Source ◽  
Copper Concentration ◽  
Copper Ion ◽  
Taxonomic Composition ◽  
Electron Donors ◽  
The Other ◽  
Copper Sulphide ◽  
Mineral Phases ◽  
Reducing Bacteria

Abstract Sulphidogenous microorganism communities were isolated from soil polluted by crude oil. The study was focused on determining the influence of 1) copper (II) concentration on the activity of selected microorganism communities and 2) the applied electron donor on the course and evolution of mineral-forming processes under conditions favouring growth of sulphate-reducing bacteria (SRB). The influence of copper concentration on the activity of selected microorganism communities and the type of mineral phases formed was determined during experiments in which copper (II) chloride at concentrations of 0.1, 0.2, 0.5 and 0.7 g/L was added to SRB cultures. The experiments were performed in two variants: with ethanol (4 g/L) or lactate (4 g/L) as the sole carbon source. In order to determine the taxonomic composition of the selected microorganism communities, the 16S rRNA method was used. Results of this analysis confirmed the presence of Desulfovibrio, Desulfohalobium, Desulfotalea, Thermotoga, Solibacter, Gramella, Anaeromyxobacter and Myxococcus sp. in the stationary cultures. The post-culture sediments contained covelline (CuS) and digenite (Cu9S5 ). Based on the results, it can be stated that the type of carbon source applied during incubation plays a crucial role in determining the mineral composition of the post-culture sediments. Thus, regardless of the amount of copper ion introduced to a culture with lactate as the sole carbon source, no copper sulphide was observed in the post-culture sediments. Cultures with ethanol as the sole carbon source, on the other hand, yielded covelline or digenite in all post-culture sediments.

scholarly journals Transformation of Isopropylamine to l-Alaninol by Pseudomonas sp. Strain KIE171 Involves N-Glutamylated Intermediates

2002 ◽  
Vol 68 (5) ◽  
pp. 2368-2375 ◽  
Author(s):  
Susana I. de Azevedo Wäsch ◽  
Jan R. van der Ploeg ◽  
Tere Maire ◽  
Alice Lebreton ◽  
Andreas Kiener ◽  
...  
Keyword(s):  
Enzymatic Hydrolysis ◽  
Carbon Source ◽  
Alcohol Dehydrogenase ◽  
Sole Carbon Source ◽  
The Other ◽  
Pseudomonas Sp ◽  
Component System ◽  
Aldehyde Dehydrogenases ◽  
Transposon Insertion ◽  
Do So

ABSTRACT Pseudomonas sp. strain KIE171 was able to grow with isopropylamine or l-alaninol [S-(+)-2-amino-1-propanol] as the sole carbon source, but not with d-alaninol. To investigate the hypothesis that l-alaninol is an intermediate in the degradation of isopropylamine, two mini-Tn5 mutants unable to utilize both isopropylamine and l-alaninol were isolated. Whereas mutant KIE171-BI transformed isopropylamine to l-alaninol, mutant KIE171-BII failed to do so. The two genes containing a transposon insertion were cloned, and the DNA regions flanking the insertions were sequenced. Two clusters, one comprising eight ipu (isopropylamine utilization) genes (ipuABCDEFGH) and the other encompassing two genes (ipuI and orf259), were identified. Comparisons of sequences of the deduced Ipu proteins and those in the database suggested that isopropylamine is transported into the cytoplasm by a putative permease, IpuG. The next step, the formation of γ-glutamyl-isopropylamide from isopropylamine, ATP, and l-glutamate, was shown to be catalyzed by IpuC, a γ-glutamylamide synthetase. γ-Glutamyl-isopropylamide is then subjected to stereospecific monooxygenation by the hypothetical four-component system IpuABDE, thereby yielding γ-glutamyl-l-alaninol [γ(l-glutamyl)-l-hydroxy-isopropylamide]. Enzymatic hydrolysis by a hydrolase, IpuF, was shown to finally liberate l-alaninol and to regenerate l-glutamate. No gene(s) encoding an enzyme for the next step in the degradation of isopropylamine was found in the ipu clusters. Presumably, l-alaninol is oxidized by an alcohol dehydrogenase to yield l-2-aminopropionaldehyde or it is deaminated by an ammonia lyase to propionaldehyde. Genetic evidence indicated that the aldehyde formed is then further oxidized by the hypothetical aldehyde dehydrogenases IpuI and IpuH to either l-alanine or propionic acid, compounds which can be processed by reactions of the intermediary metabolism.

Turnover and Distribution of 131Iodine-Labelled Human Fibrinogen

1964 ◽  
Vol 11 (02) ◽  
pp. 404-422 ◽  
Author(s):  
Annemarie Amris ◽  
C. J Amris
Keyword(s):  
Body Weight ◽  
Cancer Patient ◽  
Distribution Ratio ◽  
Half Life ◽  
Fibrinolytic Activity ◽  
The Other ◽  
Turnover Rates ◽  
Human Fibrinogen ◽  
Coagulation Defects ◽  
Fractional Turnover

Summary14 patients (5 diabetics with arteriosclerotic complications, 4 patients with thrombo-embolic disease, 4 with cirrhosis, coagulation defects and increased fibrinolytic activity, and 1 cancer patient) and 3 control patients were subjected to turnover studies with 13iodine labelled human fibrinogen.Half-life times in the control patients were found to be 4 days, the fractional turnover rates 19–23 per cent, of intravascular fibrinogen per day, and the absolute turnover 0.02 to 0.06 gm per day per kg. body weight. The other patient’s half-life times and turnover rates varied considerably from 0.9–5.5 days, 13–160 per cent, per day of intravascular fibrinogen and 0.02–0.4 gm per day per kg. body weight respectively.As fibrinogen unlike other proteins subjected to turnover studies, is converted to fibrin, it is not possible to measure the true intra-extravascular distribution ratio of fibrinogen. But intravascular fibrinogen could be approximated to constitute 68–99 per cent, of the total fibrinogen. There is justification in believing that fibrinogen is degradated through a continuous coagulation in equilibrium with fibrinolysis, and that the organism contains a greater mass of fibrin, the “fibrin pool”. Considerations of the turnover mechanism can however only be hypothetical.

Examination for Degradation Paths of Butyltin Compounds in Natural Waters

1992 ◽  
Vol 25 (11) ◽  
pp. 117-124 ◽  
Author(s):  
N. Watanabe ◽  
S. Sakai ◽  
H. Takatsuki
Keyword(s):  
Glass Fiber ◽  
Half Life ◽  
Natural Waters ◽  
Sea Water ◽  
Degradation Process ◽  
Distilled Water ◽  
Degradation Rates ◽  
Clean Area ◽  
Butyltin Compounds ◽  
Sun Light

Examination of individual degradation paths (biodegradation and photolysis) of butyltin compounds (especially tributyltin: TBT) in natural waters was performed. Biodegradation of TBT and dibutyltin (DBT) in an unfiltered sea water in summer is rather fast; their half life is about a week. But pretreatment with glass fiber filter makes the half life of TBT much longer (about 80 days). Photolysis of TBT in sea water by sun light is rapid (half life is about 0.5 days), and faster than in distilled water or in fresh water. Degradation rates of each process for TBT are calculated in various conditions of sea water, and contribution rates are compared. Biodegradation will be the main degradation process in an “SS-rich” area such as a marina, but photolysis will exceed that in a “clean” area. Over all half lives of TBT in sea water vary from 6 days to 127 days considering seasons and presence of SS.

scholarly journals Pandrug-resistant Pseudomonas sp. expresses New Delhi metallo-β-lactamase-1 and consumes ampicillin as sole carbon source

2020 ◽  
Author(s):  
Vivek Kumar Ranjan ◽  
Shriparna Mukherjee ◽  
Subarna Thakur ◽  
Krutika Gupta ◽  
Ranadhir Chakraborty
Keyword(s):  
Carbon Source ◽  
Sole Carbon Source ◽  
New Delhi ◽  
Pseudomonas Sp
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