Oxygen concentration affects frequency and range of transconjugants for the incompatibility (Inc) P-1 and P-7 plasmids pBP136 and pCAR1

ABSTRACT The frequency of transconjugants were compared for the incompatibility (Inc) P-1 and P-7 plasmids pBP136 and pCAR1 under aerobic and anaerobic conditions. Filter mating assays were performed with one donor strain and one recipient strain using different donors of Pseudomonas and recipient strains, including Pseudomonas, Pantoea, and Buttiauxella. Under anaerobic condition, frequencies of transconjugants for both plasmids were 101-103-fold lower than those under aerobic condition regardless of whether aerobically or anaerobically grown donors and recipients were used. To compare the transconjugant ranges under aerobic and anaerobic conditions, conjugation was performed between the donor of pBP136 and recipient bacteria extracted from environmental samples. Several transconjugants were uniquely obtained from each aerobic or anaerobic condition. Our findings indicate that a plasmid can differently spread among bacteria depending on the oxygen concentrations of the environment.

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Incubation Studies on Exchangable Zn for Varying Levels of added Zn Under Aerobic and Anaerobic Conditions in Grey Terrace Soils, Non Calcarious Floodplain Soils and Calcarious Floodplain Soils

Journal of Science Foundation ◽

10.3329/jsf.v9i1-2.14643 ◽

2013 ◽

Vol 9 (1-2) ◽

pp. 9-15 ◽

Cited By ~ 1

Author(s):

KH Talukder ◽

IU Ahmed ◽

MS Islam ◽

M Asaduzzaman ◽

...

Keyword(s):

Anaerobic Condition ◽

Early Stage ◽

Aerobic Condition ◽

Anaerobic Conditions ◽

Floodplain Soil ◽

Zinc Fractions ◽

Floodplain Soils ◽

Soil Zn ◽

Aerobic And Anaerobic ◽

Aerobic And Anaerobic Conditions

Fractions studies were done to know how the zinc applied to different soils was distributed in to various fractions when the soils incubated under aerobic and anaerobic condition. The added zinc provided significant increase in exchangeable Zn both under aerobic and anaerobic conditions although anaerobic condition gave lower results than aerobic condition. The higher results were obtained at early stage of incubation and it gradually reduced as the incubation period proceeded to 90 days. These results showed all most similar trends for all the soils under study. In general, added zinc showed significantly higher results to the different fractions of soil Zn both under anaerobic and aerobic incubation with very few exceptions. The highest amount of added Zn (12 kg/ha) always produced greater results than the lower doses. Only exchangeable Zn was found higher in the 1st measurement at 15 DAI then gradually decreased but in other cases, gradual increase in zinc fractions was seen as the incubation study proceed to longer duration provided with very few exceptions. In many cases, the exchangeable-Zn found higher only at 15 DAI but sharply reduced at 30 DAI. In general, the Gray Terrace Soil produced the highest results followed by Non Calcareous Gray Floodplain and the lowest results were observed in Dark Grey Floodplain & Brown Floodplain Soil. DOI: http://dx.doi.org/10.3329/jsf.v9i1-2.14643 J. Sci. Foundation, 9(1&2): 9-15, June-December 2011

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The Influences of Aerobic and Anaerobic Conditions on PHB and Glycerin Yields in the Process of Lignin Degradation by Pseudomonas stutzeri P156

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.634-638.1170 ◽

2013 ◽

Vol 634-638 ◽

pp. 1170-1174 ◽

Cited By ~ 1

Author(s):

Zhi Wang ◽

Wei Zi Qin ◽

Shuai Shuai Bao ◽

Xiong Chen ◽

Feng Lian Zhang ◽

...

Keyword(s):

Anaerobic Condition ◽

Degradation Rate ◽

Lignin Degradation ◽

Lignin Content ◽

Aerobic Condition ◽

Pseudomonas Stutzeri ◽

Anaerobic Conditions ◽

The Cost ◽

Aerobic And Anaerobic ◽

Aerobic And Anaerobic Conditions

The effects of aerobic and anaerobic conditions on polyhydroxybutyrate (PHB) and glycerin yields during the course of lignin degradation were studied with Pseudomonas stutzeri P156. The lignin degradation rate was 22.5% and 15%, respectively, under aerobic and anaerobic condition. However, the gradation rate/biomass (YL/X) was nearly no differences that diversified from 0.9% to 3%. In addition, the maximal anaerobic yield of PHB and glycerin yield was 0.42 g/g and 56.3 ug/ml, which was 176.6% and 36.7% higher than that under aerobic condition, respectively. Interestingly to point out, anaerobic lignin degradation rate was decreased by 33.3% relative to the aerobic one, but lignin content did decreased by 15% at the cost of higher yields of PHB and glycerin, which suggested biosyntheses of PHB and glycerin could balance the redox potential under anaerobic condition, facilitate lignin degradation by Pseudomonas stutzeri P156, persistently, and meet the process demands of straw-based anaerobic methane fermentation.

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Effect of Addition of Tryptophan on Aggregation of Apo-α-Lactalbumin Induced by UV-Light

Foods ◽

10.3390/foods10071577 ◽

2021 ◽

Vol 10 (7) ◽

pp. 1577

Author(s):

Zichen Zhao ◽

Renjie Li ◽

Mahesha M. Poojary ◽

Søren B. Nielsen ◽

Marianne N. Lund

Keyword(s):

Uv Light ◽

Bond Cleavage ◽

Aerobic Condition ◽

Amino Acid Residues ◽

Exchange Reactions ◽

Anaerobic Conditions ◽

Aerobic Conditions ◽

Induced Aggregation ◽

Aerobic And Anaerobic ◽

Aerobic And Anaerobic Conditions

UV-B illumination facilitates aggregation of alpha-lactalbumin (α-LA) by intramolecular disulfide bond cleavage followed by intermolecular thiol-disulfide exchange reactions. However, long term exposure to UV-B illumination may induce undesired oxidative modifications of amino acid residues in the protein. The purpose of this study was to examine the effect of UV-induced aggregation of apo-α-LA (a calcium-depleted form of α-LA) under aerobic and anaerobic conditions and by addition of tryptophan (Trp) as a photosensitizer. The addition of Trp to apo-α-LA illuminated under anaerobic conditions facilitated the highest level of free thiol release and disulfide-mediated aggregation as compared to without addition of Trp under both anaerobic and aerobic conditions. Addition of Trp under aerobic condition resulted in the lowest level of free thiols and disulfide-mediated aggregation and the aerobic conditions caused oxidation of the free Trp with formation of kynurenine and 5-hydroxy-Trp. Minor levels of the Trp oxidation product, 3-hydroxy-kynurenine (2% converted from Trp), was formed in apo-α-LA with added Trp under both aerobic and anaerobic conditions after UV-B treatment.

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ATTENUATION OF HEAVY METALS IN SEDIMENTS OF THE BONNY ESTUARY, NIGERIA: THE ROLE OF OXYGEN

JOURNAL OF ADVANCES IN CHEMISTRY ◽

10.24297/jac.v9i1.2305 ◽

2013 ◽

Vol 9 (1) ◽

pp. 1810-1821

Author(s):

Dr. Dike Henry Ogbuagu ◽

Dagogo Eras Dinney

Keyword(s):

Pearson Correlation ◽

Aerobic Condition ◽

Significant Heterogeneity ◽

Anaerobic Conditions ◽

Student’S T ◽

Aerobic And Anaerobic ◽

Aerobic And Anaerobic Conditions ◽

Student’S T Test ◽

Analyze Data

Sediments of the Bonny Estuary, which is repository to pollutants from various industrial and shipment activities in its catchment was investigated for rate of natural attenuation of toxic metals (Cd, Mn, Cr, Pb, Cu, Ni, Fe) under aerobic and anaerobic conditions. Samples were collected with pre-grab sampler from seabed, sieved in the laboratory and monitored under aerobic and anaerobic conditions. After incubation at 18°C, harvests were made on days 1, 14, 28 and 42 and levels of the metals determined spectrophotometrically. Variation plots, ANOVA, Means plots, Student’s t-test and Pearson correlation (r) were used to analyze data. Concentration reductions were higher in aerobic condition in the order Cu(15.5%)> Cd(11.4%)> Fe(8.0%)>Mn(5.7%)> Cr(4.4%)> Ni(4.2%)>Pb(3.9%) than in anaerobic condition which was in the order Cu(7.5%)> Cd(7.4%)>Pb(2.4%)>Mn/Cr(1.8% each)> Fe(0.9%)> Ni(0.5%). There was significant heterogeneity in metals reductions (Sig. F=0.000) on all the harvest days, especially of Cu, Pb and Fe at P<0.05. Attenuation of Mn also differed markedly between the aerobic and anaerobic conditions (Sig. t=0.005) at the 95% confidence interval. pH influenced the attenuation of Ni (r=0.766) and Fe (r=0.795) (P<0.05) as well as Cd (r=0.968), Cr (r=0.861), Pb (r=0.989) and Cu (r=0.950) (P<0.01). Results indicate that rate of attenuation was slow and slightly enhanced by oxygenation.

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