• KSBB Journal
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• v.13 no.4
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• pp.449-455
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• 1998

The bacterial motility in sand was studied with Alcaligenes xylosoxidans Y234 which is known as a strong decomposer of aromatic chemicals, especially toluene. Apparent motility coefficient (${\mu}$c,app) and apparent chemotaxis coefficient (${\mu}$c,app) for toluene were measured in the sands which have four different porosities. Adsorption ratio of Alcaligenes xylosoxidans Y234 on the sands was measured as 17%. The ramdom motility coefficients were 0.85∼1.68${\times}$10-3$\textrm{cm}^2$/sec, and decreased as the porosity of sands decreased. Apparent chemotaxis coefficients were measured as 1.1∼6.8${\times}$10-5$\textrm{cm}^2$/sec, and decreased as the porosity decreased and with time. The tendency of alcaligenes xylosoxidans Y234 movement towards toluene seemed very weak and showed little chemotaxis.

• Microbiology and Biotechnology Letters
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• v.22 no.4
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• pp.423-429
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• 1994

A bacterial strain which formed a distinct colony on agar plate containing naphthalene as a vapor phase and grew well ina liquid minimal medium was isolated and identified as Alcaligenes sp. A111. Optimum temperature and pH for the cultivation of Alcaligenes sp. A111 were 30$\cir$C and 7.0, respectively. Cell growth increased dramatically from 12 hours after inoculation and revealed a stationary phase at about 48 hours. Relative growth rate ($\mu$')increased hyperbolically depending on the conceration of naphthalene up to 500 ppm and reached to the maximum value pf 2.8/day, but $\mu$' didn't change within a range of 500~4000 ppm naphthalene. NH$_{4}$Cl or NH$_{4}$NO$_{3}$ was preferrd as a nitrogen source and a P : N ratio by weight og 6 : 1 was favorable to cell growth. Alcaligenes sp. A111 utilized the intermediates of degradation of naphthalene and showed tolerance to benzene, toluene, and octane. therefore, it is suggested that Alcaligenes sp. A111 could be effectively used for the biological treatment of wastewater containing naphthalene in the presence of some aromatic compounds.

• The Korean Journal of Mycology
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• v.44 no.3
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• pp.171-175
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• 2016

A gram-negative bacterium was isolated from spent substrates of Agaricus bisporus and showed significant antagonistic activity against Pseudomonas agarici. The bacterium was identified as Alcaligenes sp. based on cultural, biochemical, physiological characteristics and a 16S rRNA sequence analysis. The isolate is saprophytic, but not parasitic or pathogenic on cultivated mushroom, whereas it showed strong inhibitory effects against P. agarici cells in vitro. The control efficacy of Alcaligenes sp. HC12 against brown blotch of P. agarici was up to 63% on Agaricus bisporus. The suppressive bacterium may be useful for the development of biocontrol systems.

• Journal of Life Science
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• v.9 no.4
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• pp.414-422
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• 1999

Our works performed for preparation of oligosaccharides from carrageenan, seaweed polysaccharide, and one active strain for carrageenan was isolated from sea water and identified to Pseudomonas alcaligenes. Carrageenan degrading enzyme was purified from the culture fluid of isolated strain-Pseudomonas alcaligenes JCL-43, by DEAE-Cellulose, Sephadex G-100, Q-Sepharose and CM Sepharose CL-6B column chromatography. Two enzyme-F-I, F-II- was identified this purifying process, and the molecular weight of the purified carrageenase were estimated to be 23.6kDa and 30.2kDa, respectively. The optimum pH and temperature for two carrageenase activity were 7.0 and 4$0^{\circ}C$. These enzymes were stable in the pH range of 6.0~7.5 and lower than 5$0^{\circ}C$, and required 1.5% NaCl for optimum activity. And these carragennase were inhibited by metal ions such as Cu2+, Zn2+, Hg2+, but increased by Ba2+ and Ca2+, and showed specificity on -carrageenan.

• Microbiology and Biotechnology Letters
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• v.22 no.4
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• pp.401-406
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• 1994

The medium compositions of Alcaligenes eutrophus were optimized for increasing PHB productivity. It is very important to optimize the concentrations of inorganic salts and trace eleme- nts as well as carbon and nitrogen sources to maximize cell growth rate and productivity. The fed-batch culture of Alcaligenes eutrophus by dual feeding of ammonia water and glucose under optimized initial medium concentrations was carried out. Glucose was fed manually according to glucose consumption rate and ammonia water by pH-stat. The final cell concentrations and PHB content in 30 hours were 122 g/l and 65% of dry cell weight(yielding 79 g of PHB/l), respectively and 2.64 g/l/hr of PHB production rate was obtained.

• Journal of Microbiology and Biotechnology
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• v.6 no.5
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• pp.309-314
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• 1996

Alcaligenes sp. SH-69 can synthesize poly(3-hydroxybutyrate-co-3-hydroxyvalerate) from a single carbon source such as glucose. To clone the phaC gene from Alcaligenes sp. SH-69, a polymerase chain reaction was performed using the oligomers synthesized based on the conserved regions of the phaC genes from other bacteria. A PCR product (550 bp) was partially sequenced and the deduced amino acid sequence was found to be homologous to that of the phaC gene from Alcaligenes eutrophus. Using the PCR fragment Southern blotting of Alcaligenes sp. SH-69 genomic DNA digested with several restriction enzymes was carried out. To prepare a partial genomic library, about 5-Kb genomic DNA fragments digested with EcoRI, which showed a positive signal in the Southern blotting, were eluted from an agarose gel, ligated with pUC19 cleaved with EcoRI, and transformed into Escherichia coli. The partial library was screened using the PCR fragment as a probe and a plasmid, named pPHA11, showing a strong hybridization signal was selected. Restriction mapping of the insert DNA in pPHA11 was performed. Cotransformation into E. coli of the plasmid pPHA11 and the plasmid pPHA21 which has phaA and phaB from A. eutrophus resulted in turbid E. coli colonies which are indicative of PHA accumulation. This result tells us that the Alcaligenes sp. SH-69 phaC gene in the pPHA11 is functionally active in E. coli and can synthesize PHA in the presence of the A. eutrophus phaA and phaB genes.

• Microbiology and Biotechnology Letters
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• v.39 no.2
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• pp.182-187
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• 2011

In this study, A bacterium with an ability to resist toxic heavy metals was isolated from reeds in wetland. The isolated strain was identified to Alcaligenes sp. KC-1 by 16S rDNA sequencing. Heavy metals such as Pb, $Cr^{6+}$, Cd, Zn and Cu were supplied to media. The ecotoxic treat of the heavy metals on the growth of strain KC-1 was performed when the isolated strain Alcaligenes sp. KC-1 cultured with Cu ranging from 0 mM to 20 mM. It showed the resistance of $EC_{50}$(7.34 mM) and cell growth ($OD_{600\;nm}$ : 0.83 after 42 hours) when it was cultured in Cu.

• Microbiology and Biotechnology Letters
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• v.15 no.6
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• pp.375-380
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• 1987

D-$\alpha$-Amino-$\varepsilon$-carpolactam racemase (EC 5.1.1) and L-$\alpha$-amino-$\varepsilon$-caprolactam hydrolase (EC 3.5.2) were fractionated from cell-free extracts of Alcaligenes eutrophus A52 using ammonium sulfate precipitation and DEAE-cellulose ion exchange chromatography. It was made sure that D-$\alpha$-amino-$\varepsilon$-caprolactam was converted to L-$\alpha$-amino-$\varepsilon$-caprolactam by racemase, and then hydrolyzed into L-lysine by hydrolase in Alcaligenes eutrophus A52. For the conversion of D-$\alpha$-amino-$\varepsilon$-caprolactam into L-lysine by cell-free extracts of Alcaligenes eutrophus A52, the optimum temperature and pH were 6$0^{\circ}C$ and 8.5 respectively. The results showed that 0.5% D-$\alpha$-amino-$\varepsilon$-caprolactam was converted to L-lysine at 55$^{\circ}C$ for 10 hr with a conversion rate of 98% by cell-free extracts containing 3.1mg of protein.

• Journal of Mushroom
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• v.14 no.4
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• pp.191-196
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• 2016

This study was conducted to investigate optimum conditions for mass production of ntagonistic microbes Alcaligenes sp. HC12. Alcaligenes sp. HC12 had a potent biological control agent to control browning disease caused by Pseudomonas agarici. Alcaligenes sp. HC12 markedly showed the antagonistic activity against Pseudomonas agarici, the most destructive pathogen of cultivated mushrooms. To define the optimum conditions for the mass production of the Alcaligenes sp. HC12, we have investigated optimum culture conditions and effects of various nutrient source on the bacterial growth. The optimum initial pH and temperature were determined as pH 9.0 and $30^{\circ}$, respectively. The optimal concentration of medium elements for the growth of pathogen inhibitor bacterium(Alcaligenes sp. HC12) was determined as follows: 0.5% dextrine, 1.5% yest extract, 1.0% $NaNO_3$, 0.5% $KH_2PO_4$, and 1.5% asparagine.

• Korean Journal of Environmental Agriculture
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• v.30 no.2
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• pp.216-222
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• 2011

BACKGROUND: This study was performed to evaluate the effects of environmental factors and heavy metals on the growth and phosphorus removal capacity of Alcaligenes sp., which was well known as one of PAOs(Phosphorus Accumulating Microorganisms). METHODS AND RESULTS: The environmental factors used in this study were temperature, pH and carbon sources, and the heavy metals included Cu, Cd, Zn, As, and Ni. The growth and P removal efficiency of Alcaligenes sp. was maximal as temperature, pH, and carbon source were $25^{\circ}C$, 7, and glucose+acetate, respectively. Also, the $IC_{50}$(median inhibitory Concentration) values of Alcaligenes sp. for the Cu, Cd, Zn, As, and Ni were 5.03, 0.08, 0.73, 282.20 and 4.74 mg/L, respectively. CONCLUSION(S): Based on the results obtained from this study, it appears that the growth and P removal efficiency of Alcaligenes sp. were affected by the environment factors and at the best optimum condition for its growth and P removal efficiency, as the concentrations of heavy metals were gradually increased, its growth was correspondingly decreased.