Journal of Microbiology

Hyung-Yeel Kahng

11 Articles

Cyclobacterium sediminis sp. nov. isolated from a sea cucumber aquaculture farm and emended description of the genus Cyclobacterium: Seyeon Shin , Hyung-Yeel Kahng; J. Microbiol. 2017;55(2):90-95. Published online January 26, 2017; DOI: https://doi.org/10.1007/s12275-017-6484-6

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An aerobic, Gram-negative bacterium, designated strain SD70T, was isolated from sea cucumber aquaculture farm sediment in Taean, Korea, and its taxonomic status was established by undertaking a polyphasic study. Cells of strain SD70T were non-motile, catalase-, and oxidase-positive, nonspore- forming, and horseshoe-shaped. Optimal growth was observed under 25–30°C, pH 7.0–8.0, and 3.0–5.0% (w/v) NaCl conditions. Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain SD70T fell within an evolutionary group comprising species of the genus Cyclobacterium. Strain SD70T shared 92.1–98.5% 16S rRNA sequence similarity values with the type strains of species of the genus Cyclobacterium. Relatively low levels of DNA-DNA relatedness were found between strain SD70T and C. marinum DSM 745T (40.2%) and C. amurskyense KMM 6143T (15.8%). The predominant cellular fatty acids were iso-C15:0 (32.1%), and anteiso-C15:0 (9.1%). Menaquinone MK-7 was the only respiratory quinone. The G+C content of the genomic DNA was 36 mol%. The polar lipids were phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, and seven unidentified lipids. On the basis of phenotypic and genotypic data, strain SD70T represents a novel species of the genus Cyclobacterium, for which the name Cyclobacterium sediminis sp. nov. is proposed. An emended description of the genus Cyclobacterium is also provided.

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Validation list no. 225: valid publication of new names and new combinations effectively published outside the IJSEM
Aharon Oren, Markus Göker
International Journal of Systematic and Evolutionary Microbiology .2025;[Epub] CrossRef
Taxogenomics of the Genus Cyclobacterium: Cyclobacterium xiamenense and Cyclobacterium halophilum as Synonyms and Description of Cyclobacterium plantarum sp. nov.
Azadeh Shahinpei, Mohammad Ali Amoozegar, Leila Mirfeizi, Mahdi Moshtaghi Nikou, Antonio Ventosa, Cristina Sánchez-Porro
Microorganisms.2020; 8(4): 610. CrossRef
Cyclobacterium salsum sp. nov. and Cyclobacterium roseum sp. nov., isolated from a saline lake
Yong-Hong Liu, Yuan-Guo Xie, Li Li, Hong-Chen Jiang, Osama Abdalla Abdelshafy Mohamad, Wael Hozzein, Bao-Zhu Fang, Wen-Jun Li
International Journal of Systematic and Evolutionary Microbiology .2020; 70(6): 3785. CrossRef
Glacial-interglacial transitions in microbiomes recorded in deep-sea sediments from the western equatorial Atlantic
Lucas Freitas, Luciana Appolinario, Gabriela Calegario, Mariana Campeão, Diogo Tschoeke, Gizele Garcia, Igor Martins Venancio, Carlos A.N. Cosenza, Luciana Leomil, Marcelo Bernardes, Ana Luiza Albuquerque, Cristiane Thompson, Fabiano Thompson
Science of The Total Environment.2020; 746: 140904. CrossRef
Analysis of 1,000 Type-Strain Genomes Improves Taxonomic Classification of Bacteroidetes
Marina García-López, Jan P. Meier-Kolthoff, Brian J. Tindall, Sabine Gronow, Tanja Woyke, Nikos C. Kyrpides, Richard L. Hahnke, Markus Göker
Frontiers in Microbiology.2019;[Epub] CrossRef
Notification of changes in taxonomic opinion previously published outside the IJSEM
Aharon Oren, George M. Garrity
International Journal of Systematic and Evolutionary Microbiology .2017; 67(7): 2081. CrossRef

Aquimarina litoralis sp. nov., Isolated from a Coastal Seawater: You-Sung Oh , Hyung-Yeel Kahng , Young Sun Lee , Byoung-Jun Yoon , Sang-Bin Lim , Jae Sung Jung , Duck-Chul Oh , Dong-Heon Lee; J. Microbiol. 2010;48(4):433-437. Published online August 20, 2010; DOI: https://doi.org/10.1007/s12275-010-0088-8

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A strictly aerobic, red-pigmented, non-motile, catalase- and oxidase-positive, Gram-staining-negative bacterium, designated strain CNURIC011T, was isolated from seawater off the coast of Jeju Island in Korea. A phylogenetic analysis based on 16S rRNA gene sequences showed that strain CNURIC011T belongs to the genus Aquimarina in the family Flavobacteriaceae. 16S rRNA gene sequence analysis revealed that the close relatives of the novel strain are Aquimarina latercula ATCC 23177T, Aquimarina marcrocephali JAMB N27T, Aquimarina intermedia KMM 6258T, Aquimarina muelleri KMM 6020T, and Aquimarina brevivitae SMK-19T, with sequence similarities of 97.6, 96.6, 96.0, 95.6, and 94.2%, respectively. DNA-DNA hybridization revealed that the level of relatedness between strain CNURIC011T and Aquimarina latercula ATCC 23177T (=KCTC 2912T) was 4.9%. The DNA G+C content was 35.8 mol% and the major respiratory quinone was MK-6. The major fatty acids were iso-C15:0 (14.9%), C15:0 (13.9%), iso-C17:0 3-OH (12.6%), iso-C15:1 G (7.3%), and iso-C17:1 ω9c (7.2%). On the basis of phenotypic, phylogenetic, and genotypic data, strain CNURIC011T represents a novel species within the genus Aquimarina, for which the name Aquimarina litoralis sp. nov. is proposed. The type strain is CNURIC011T (=KCTC 22614T =JCM 15974T).

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Aquimarina ulvae sp. nov. and Polaribacter litoreus sp. nov., isolated from the green alga Ulva prolifera
Sylvia Kristyanto, Jiyoung Woo, Keun-Hyung Choi
International Journal of Systematic and Evolutionary Microbiology .2026;[Epub] CrossRef
Validation List no. 222. Valid publication of new names and new combinations effectively published outside the IJSEM
Aharon Oren, Markus Göker
International Journal of Systematic and Evolutionary Microbiology .2025;[Epub] CrossRef
Insights into the Antimicrobial Activities and Metabolomes of Aquimarina (Flavobacteriaceae, Bacteroidetes) Species from the Rare Marine Biosphere
Sandra Godinho Silva, Patrícia Paula, José Paulo da Silva, Dalila Mil-Homens, Miguel Cacho Teixeira, Arsénio Mendes Fialho, Rodrigo Costa, Tina Keller-Costa
Marine Drugs.2022; 20(7): 423. CrossRef
Insights into the genomic repertoire of Aquimarina litoralis CCMR20, a symbiont of coral Mussismilia braziliensis
Tooba Varasteh, Diogo Tschoeke, Gizele Garcia, Arthur Silva Lima, Ana Paula B. Moreira, Cristiane Thompson, Fabiano Thompson
Archives of Microbiology.2021; 203(5): 2743. CrossRef
Aquimarina sp. Associated With a Cuticular Disease of Cultured Larval Palinurid and Scyllarid Lobsters
Mei C. Ooi, Evan F. Goulden, Andrew J. Trotter, Gregory G. Smith, Andrew R. Bridle
Frontiers in Microbiology.2020;[Epub] CrossRef
Comparative genome analysis provides novel insight into the interaction of Aquimarina sp. AD1, BL5 and AD10 with their macroalgal host
Jennifer Hudson, Vipra Kumar, Suhelen Egan
Marine Genomics.2019; 46: 8. CrossRef
Real-time PCR assay for Aquimarina macrocephali subsp. homaria and its distribution in shell disease lesions of Homarus americanus, Milne-Edwards, 1837, and environmental samples
Robert A. Quinn, Suchandra Hazra, Roxanna Smolowitz, Andrei Y. Chistoserdov
Journal of Microbiological Methods.2017; 139: 61. CrossRef
Aquimarina seongsanensis sp. nov., isolated from sea water
Yoojin Oh, Bong-geun Choi, Joon Yong Kim, Seong Woon Roh, Sung-Jae Lee
Antonie van Leeuwenhoek.2017; 110(8): 1019. CrossRef
Aquimarina aggregata sp. nov., isolated from seawater
Yan Wang, Hong Ming, Weiyun Guo, Hongli Chen, Chenyan Zhou
International Journal of Systematic and Evolutionary Microbiology.2016; 66(9): 3406. CrossRef
Aquimarina atlantica sp. nov., isolated from surface seawater of the Atlantic Ocean
Guizhen Li, Qiliang Lai, Fengqin Sun, Xiupian Liu, Yunbiao Xie, Yaping Du, Guangyu Li, Zongze Shao
Antonie van Leeuwenhoek.2014; 106(2): 293. CrossRef
Aquimarina amphilecti sp. nov., isolated from the sponge Amphilectus fucorum
Jonathan Kennedy, Lekha Menon Margassery, Niall D. O’Leary, Fergal O’Gara, John Morrissey, Alan D. W. Dobson
International Journal of Systematic and Evolutionary Microbiology .2014; 64(Pt_2): 501. CrossRef
Aquimarina penaei sp. nov., isolated from intestinal tract contents of Pacific white shrimp, Penaeus vannamei
Xiaoyi Li, Liping Wang, Hui Huang, Qiliang Lai, Zongze Shao
Antonie van Leeuwenhoek.2014; 106(6): 1223. CrossRef
Aquimarina agarilytica sp. nov., an agarolytic species isolated from a red alga
Bokun Lin, Guoyong Lu, Yandan Zheng, Wei Xie, Shengkang Li, Zhong Hu
International Journal of Systematic and Evolutionary Microbiology.2012; 62(Pt_4): 869. CrossRef

Gaetbulibacter jejuensis sp. nov., Isolated from Seawater: You-Sung Oh , Sang-Bin Lim , Hyung-Yeel Kahng , Byoung-Jun Yoon , Duck-Chul Oh , Jae-Ho Joa , Dong-Heon Lee; J. Microbiol. 2010;48(3):307-311. Published online June 23, 2010; DOI: https://doi.org/10.1007/s12275-010-9232-8

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A novel marine bacterium, designated strain CNURIC014T was isolated from coastal seawater of Jeju Island in Korea. Strain CNURIC014T formed yellow colonies on marine agar 2216 and the cells were Gram-negative, non-motile, strictly aerobic, rod-shaped. The temperature, pH and NaCl ranges for growth were 15-37°C, pH 6.0-9.0 and 1.0-7.0% NaCl. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain CNURIC014T was most closely related to Gaetbulibacter marinus and Gaetbulibacter saemankumensis, with a sequence similarity of 95.1% and 94.6%, respectively. The DNA G+C content of the strain was 33.1 mol% and the major respiratory quinone was menaquinone-6. The major cellular fatty acids were iso-C15:1 (22.8%), iso-C15:0 (18.8%), summed feature 3 (iso-C15:0 2-OH/C16:1 ω7c, 12.9%) and iso-C17:0 3-OH (11.5%). On the basis of phenotypic, phylogenetic, and genotypic data, strain CNURIC014T represents a novel species within the genus Geatbulibacter, for which the name Gaetbulibacter jejuensis sp. nov. is proposed. The type strain is CNURIC014T (=KCTC 22615T =JCM 15976T).

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Validation List no. 222. Valid publication of new names and new combinations effectively published outside the IJSEM
Aharon Oren, Markus Göker
International Journal of Systematic and Evolutionary Microbiology .2025;[Epub] CrossRef
Genome sequence of Gaetbulibacter sp. PBL-D1 isolated from a Malaysian beach: insights into glycoside hydrolase repertoires
Ummirul Mukminin Kahar, Najiha Atiqah Md Nor, Wan Nur Izrena Wan Izanni
BMC Genomic Data.2025;[Epub] CrossRef
Analysis of components according to different collecting time and production method in sun-dried salt
Yong-Xie Jin, Haeng-Ryan Kim, So-Young Kim
Korean Journal of Food Preservation.2013; 20(6): 791. CrossRef

Comparative Analysis of 2,4,6-Trinitrotoluene (TNT)-Induced Cellular Responses and Proteomes in Pseudomonas sp. HK-6 in Two Types of Media: Yun-Seok Cho , Bheong-Uk Lee , Hyung-Yeel Kahng , Kye-Heon Oh; J. Microbiol. 2009;47(2):220-224. Published online May 2, 2009; DOI: https://doi.org/10.1007/s12275-008-0108-0

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TNT-induced cellular responses and proteomes in Pseudomonas sp. HK-6 were comparatively analyzed in two different media: basal salts (BS) and Luria broth (LB). HK-6 cells could not degrade more than 0.5 mM TNT with BS medium, while in LB medium, they exhibited the enhanced capability to degrade as much as 3.0 mM TNT. Analysis of total cellular fatty acids in HK-6 cells suggested that the relative abundance of several saturated or unsaturated fatty acids is altered under TNT-mediated stress conditions. Scanning electron microscopy showed the presence of perforations, irregular rod formations, and wrinkled extracellular surfaces in cells under TNT stress. Proteomic analysis of soluble protein fractions from HK-6 <br>cultures grown with TNT as a substrate revealed 11 protein spots induced by TNT. Among these, seven proteins (including Alg8, AlgB, NirB, and the AhpC/Tsa family) were detected only in LB medium containing TNT. The proteins AspS, Tsf, and assimilatory nitrate reductase were increasingly expressed only in BS medium containing TNT. The protein dGTPase was found to be induced and expressed when cells were grown in either type of TNT-containing media. These results provide a better understanding of the cytotoxicity and survival mechanism used by Pseudomonas sp. HK-6 when placed under TNT stress conditions.

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New insights into xenobiotic tolerance of Antarctic bacteria: transcriptomic analysis of Pseudomonas sp. TNT3 during 2,4,6-trinitrotoluene biotransformation
Ma. Ángeles Cabrera, Sebastián L. Márquez, José M. Pérez-Donoso
Environmental Science and Pollution Research.2024; 31(11): 17256. CrossRef
Bacillus pumilus proteome changes in response to 2,4,6-trinitrotoluene-induced stress
Galina Yakovleva, William Kurdy, Anna Gorbunova, Irina Khilyas, Guenter Lochnit, Olga Ilinskaya
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Improvement of Thermotolerance of Zymomonas mobilis by Genes for Reactive Oxygen Species-Scavenging Enzymes and Heat Shock Proteins
Sakunda Anggarini, Masayuki Murata, Keisuke Kido, Tomoyuki Kosaka, Kaewta Sootsuwan, Pornthap Thanonkeo, Mamoru Yamada
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The Sycamore Maple Bacterial Culture Collection From a TNT Polluted Site Shows Novel Plant-Growth Promoting and Explosives Degrading Bacteria
Sofie Thijs, Wouter Sillen, Sascha Truyens, Bram Beckers, Jonathan van Hamme, Pieter van Dillewijn, Pieter Samyn, Robert Carleer, Nele Weyens, Jaco Vangronsveld
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Species-specific differences in peroxisome proliferation, catalase, and SOD2 upregulation as well as toxicity in human, mouse, and rat hepatoma cells induced by the explosive and environmental pollutant 2,4,6-trinitrotoluene
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Proteomic Analysis of 2,4,6-Trinitrotoluene Degrading Yeast Yarrowia lipolytica
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Enhancement of microbial 2,4,6-trinitrotoluene transformation with increased toxicity by exogenous nutrient amendment
Shih-Hsiung Liang, Duen-Wei Hsu, Chia-Ying Lin, Chih-Ming Kao, Da-Ji Huang, Chih-Ching Chien, Ssu-Ching Chen, Isheng Jason Tsai, Chien-Cheng Chen
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Microbial degradation of expired slurry explosives in mines: a review
Anuradha, Biswajit Paul, Jagdish
International Journal of Environmental Studies.2015; 72(1): 117. CrossRef
A toxicological review on potential microbial degradation intermediates of 2,4,6-trinitrotoluene, and its implications in bioremediation
Muhammad Imran Khan, Jaejin Lee, Joonhong Park
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Comparative analysis of explosive RDX-induced proteomes in the Pseudomonas sp. HK-6 wild-type strain and its rpoH mutant strain
Bheong-Uk Lee, Moon-Seop Choi, Kye-Heon Oh
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Biodegradation and biotransformation of explosives
Elizabeth L Rylott, Astrid Lorenz, Neil C Bruce
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Construction of an Escherichia-Pseudomonas Shuttle Vector Containing an Aminoglycoside Phosphotransferase Gene and a lacZ'''' Gene for α-Complementation: Bheong-Uk Lee , Ja-Heon Hong , Hyung-Yeel Kahng , Kye-Heon Oh; J. Microbiol. 2006;44(6):671-673.; DOI: https://doi.org/2458 [pii]

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Abstract PDF: A new 4.87 kb Escherichia-Pseudomonas shuttle vector has been constructed by inserting a 1.27 kb DNA fragment with a replication origin of a Pseudomonas plasmid pRO1614 into the 3.6 kb E. coli plasmid pBGS18. This vector, designated pJH1, contains an aminoglycoside phosphotransferase gene (aph) from Tn903, a lacZ'''' gene for α-complementation and a versatile multiple cloning site possessing unique restriction sites for EcoRI, SacI, KpnI, SmaI, BamHI, XbaI, SalI, BspMI, PstI, SphI, and HindIII. When pJH1 was transformed into E. coli DH5α and into P. putida HK-6, it was episomally and stably maintained in both strains. In addition, the enhanced green fluorescent protein (EGFP) gene which was transcriptionally cloned into pJH1 rendered E. coli cells fluorescence when its transformants were illuminated at 488 nm.

Characterization of β-Ketoadipate Pathway from Multi-Drug Resistance Bacterium, Acinetobacter baumannii DU202 by Proteomic Approach: Sonn-Ho Park , Jae-Woo Kim , Sung-Ho Yun , Sun Hee Leem , Hyung-Yeel Kahng , Seung Il Kim; J. Microbiol. 2006;44(6):632-640.; DOI: https://doi.org/2464 [pii]

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Abstract PDF: In this study, the biodegradative activities of monocyclic aromatic compounds were determined from the multi-drug resistant (MDR) Acinetobacter baumannii, which were studied in the form of clinical isolates from a hospital in Korea. These bacteria were capable of biodegrading monocyclic aromatic compounds, such as benzoate and p-hydroxybenzoate. In order to determine which pathways are available for biodegradation in these stains, we conducted proteome analyses of benzoate and p-hydroxybenzoate-cultured A. baumannii DU202, using 2-DE/MS analysis. As genome DB of A. baumannii was not yet available, MS/MS analysis or de novo sequencing methods were employed in the identification of induced proteins. Benzoate branch enzymes [catechol 1,2-dioxygenase (CatA) and benzoate dioxygenase α subunit (BenA)] of the β-ketoadipate pathway were identified under benzoate culture condition and p-hydroxybenzoate branch enzymes [protocatechuate 3,4-dioxygenase α subunit (PcaG) and 3-carboxy-cis,cis-muconate cycloisomerase (PcaB)] of the β-ketoadipate pathway were identified under p-hydroxybenzoate culture condition, respectively, thereby suggesting that strain DU202 utilized the β-ketoadipate pathway for the biodegradation of monocyclic aromatic compounds. The sequence analysis of two purified dioxygenases (CatA and PcaGH) indicated that CatA is closely associated with the CatA of Acinetobacter radiresistance, but PcaGH is only moderately associated with the PcaGH of Acinetobacter sp. ADP1. Interestingly, the fused form of PcaD and PcaC, carboxymuconolactone decarboxylase (PcaCD), was detected on benzoate-cultured A. baumannii DU202. These results indicate that A. baumannii DU202 exploits a different β-ketoadipate pathway from other Acinetobacter species.

Molecular Detection of Catabolic Genes for Polycyclic Aromatic Hydrocarbons in the Reed Rhizosphere of Sunchon Bay: Hyung-Yeel Kahng , Kye-Heon Oh; J. Microbiol. 2005;43(6):572-576.; DOI: https://doi.org/2287 [pii]

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Abstract PDF: This study focused on detecting catabolic genes for polycyclic aromatic hydrocarbons (PAHs) distributed in the reed rhizosphere of Sunchon Bay, Korea. These marsh and mud environments were severely affected by human activities, including agriculture and fisheries. Our previous study on microbial roles in natural decontamination displayed the possibility that PAH-degrading bacteria, such as Achromobacter sp., Alcaligenes sp., Burkholderia sp. and Pseudomonas sp. play an important decontamination role in a reed rhizosphere. In order to gain further fundamental knowledge on the natural decontamination process, catabolic genes for PAH metabolism were investigated through PCR amplification of dioxygenase genes using soil genomic DNA and sequencing. Comparative analysis of predicted amino acid sequences from 50 randomly selected dioxygenase clones capable of hydroxylating inactivated aromatic nuclei indicated that these were divided into three groups, two of which might be originated from PAH-degrading bacteria. Amino acid sequences of each dioxygenase clone were a part of the genes encoding enzymes for initial catabolism of naphthalene, phenanthrene, or pyrene that might be originated from bacteria in the reed rhizosphere of Sunchon Bay.

Introduction of Saxicolous Lichens Distributed in Coastal Rocks of U-do Islet in Jeju, Korea: Hyung-Yeel Kahng , Byoung-Jun Yoon , Sung-Hyun Kim , Duck-Ja Shin , Jae-Seoun Hur , Hyun-Woo Kim , Eui-Sung Kang , Kye-Heon Oh , Young Jin Koh; J. Microbiol. 2004;42(4):292-298.; DOI: https://doi.org/2108 [pii]

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Abstract PDF: This study reports, for the first time, the ivestigation of the distribution of Korean saxicolous lichens in the coastal rocks of U-do islet, which is known as an unpolluted zone in Jeju. More than thirty lichens were obtained and investigated from the coastal rocks frequently contacted by seawater. A molecular analysis using PCR amplification of the rRNA ITS regions revealed the coastal rock lichens could be placed into 8 families and 14 genera, Ramalinaceae (Bacidia, Ramalina), Physciaceae (Buellia, Dirinaria, Phaeophyscia, Physcia, Pyxine), Lecanoraceae (Candelaria, Lecanora), Parmeliaceae (Xanthoparmelia), Graphidaceae (Graphis), Pertusariaceae (Pertusaria), Rhizocarpaceae (Rhizocarpon), and Teloschistaceae (Caloplaca), showing a diversity of lichens, with foliose (flat leaf-like), crustose (crust-like), and fruticose (miniature shrub-like) life forms might be distributed in the coastal rocks. These findings suggested the possibility that the lichens identified in the present work might be resistant to a salty environment.

Distribution of Lichen Flora on South Korea: Jae-Seoun Hur , Hiroshi Harada , Soon-Ok Oh , Kwang-Mi Lim , Eui-Sung Kang , Seung Mi Lee , Hyung-Yeel Kahng , Hyun-Woo Kim , Jae-Sung Jung , Young Jin Koh; J. Microbiol. 2004;42(2):163-167.

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Abstract PDF: After an overview on the temporary situation of the lichenology in South Korea, localities of 95 macrolichen taxa are reported for South Korea. In this revised lichen flora of South Korea, 16 species are apparently new to the territory. Voucher specimens have been deposited in the Korean Lichen Research Institute (KoLRI) at Sunchon National University in Korea, and duplicates have also been donated to the National History Museum and Institute, in Chiba, (CBM) Japan.

Cellular Responses of Pseudomonas sp. KK1 to Two-Ring Polycyclic Aromatic Hydrocarbon, Naphthalene: Hyung-Yeel Kahng; J. Microbiol. 2002;40(1):38-42.

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Abstract PDF: The strain KK1 isolated from soil contaminated with polycyclic aromatic hydrocarbons was identified as Pseudomonas sp. based on analyses by MIDI and Biolog Identification System. Cellular and physiological responses of strain KK1 to two-ring polycyclic aromatic hydrocarbon, naphthalene were evaluated using radiorespirometry, PLFAs and sequence analysis of Rieske-type iron sulfur center of dioxygenase. KK1 was found to be able to rapidly mineralize naphthalene. Notably, KK1 cells pre-grown on phenanthrene were able to mineralize naphthalene much more rapidly than naphthalene-pregrown cells. The total cellular fatty acids of KK1 were comprised of eleven C-even and two C-odd fatty acids (fatty acids < 0.2% in abundance were not considered in this calculation). Lipids 12:0 2OH, 12:0 3OH, 16:0, 18:1 6c, 18:0 increased for naphthalene-exposed cells, while lipids 18:1 7c/15:0 iso 2OH, 17:0 cyclo, 18:1 7c, 19:0 cyclo decreased. Data from Northern hybridization using a naphthalene dixoygenase gene fragment cloned out from KK1 as a probe provided the information that naphthalene dioxygenase gene was more highly expressed in cells grown on phenanthrene than naphthalene.

Analysis of Catalases from Photosynthetic Bacterium Rhodospirillum rubrum S1: Hee-Kyoung Lim , Young-Mi Kim , Dong-Heon Lee , Hyung-Yeel Kahng , Duck-Chul Oh; J. Microbiol. 2001;39(3):168-176.

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Abstract PDF: Five different types of catalases from photosynthetic bacterium Rhodospirillum rubrum S1 grown aerobically in the dark were found in this study, and designated Cat1 (350 kDa), Cat2 (323 kDa), Cat3 (266 kDa), Cat4 (246 kDa), and Cat5 (238 kDa). Analysis of native PAGE revealed that Cat2, Cat3, and Cat4 were also produced in the cells anaerobically grown in the light. It is notable that only Cat2 was expressed much more strongly in response to the anaerobic condition. Enzyme activity staining demonstrated that Cat3 and Cat4 had bifunctional catalase-peroxidase activities, while Cat1, Cat2, and Cat5 were typical monofunctional catalases. S1 cells grown aerobically in the presence of malate as the sole source of carbon exhibited an apparent catalase Km value of 10 mM and a Vmax of about 705 U/mg protein at late stationary growth phase. The catalase activity of S1 cells grown in the anaerobic environment exhibited a much lower Vmax of about 109 U/mg protein at late logarithmic growth phase. The catalytic activity was stable in the broad range of temperatures (30 C-60 C), and pH (6.0-10.0). R. rubrum S1 was much more resistant to H_2 O_2 in the stationary growth phase than in the exponential growth phase regardless of growth conditions. Cells of stationary growth phase treated with 15 mM H 2 O 2 for 1 h showed 3-fold higher catalase activities than the untreated cells. In addition, L-glutamate induced an 80-fold increase in total catalase activity of R. rubrum S1 compared with malic acid. Through fraction analyses of S1 cells, Cat2, Cat3, Cat4 and Cat5 were found in both cytoplasm and periplasm, while Cat1 was localized only in the cytoplasm.

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