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ABSTRACT: At present, acetylcholinesterase (AChE) inhibitors are the first group of drugs to treat mild to moderate Alzheimer's disease (AD). Although beneficial in improving cognitive and behavioral symptoms, the effectiveness of AChE inhibitors has been questioned since they do not delay or prevent neurodegeneration in AD patients. Therefore, in the present study, in order to develop new and effective anti-AD agents from lichen products, both the AChE inhibitory and the neuroprotective effects were evaluated. The AChE inhibitory assay was performed based on Ellman's reaction, and the neuroprotective effect was evaluated by using the MTT method on injured PC12 cells. One AChE inhibitor (IC50 = 27.1 microg/ml) was isolated by means of bioactivity-guided isolation from the extract of lichen-forming fungus Cladonia macilenta, which showed the most potent AChE inhibitory activity in previous screening experiment. It was then identified as biruloquinone by MS, and 1H- and 13C-NMR analyses. The inhibitory kinetic assay suggested that biruloquinone is a mixed-II inhibitor on AChE. Meanwhile, biruloquinone improved the viability of the H2O2- and beta-amyloid-injured PC12 cells at 1 to 25 microg/ml. The protective effects are proposed to be related to the potent antioxidant activities of biruloquinone. These results imply that biruloquinone has the potential to be developed as a multifunctional anti- AD agent.
Journal of Microbiology and Biotechnology 02/2013; 23(2):161-6. · 1.38 Impact Factor
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ABSTRACT: Two orange-colored, rod-shaped, Gram-reaction-negative, aerobic bacterial strains devoid of flagellar and gliding motility, designated strains KYW371T and KS18 were isolated from seawater collected from Gwangyang Bay, Republic of Korea. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the two strains belonged to the family Flavobacteriaceae; and that strain KYW371T was most closely related to Algibacter mikhailovii LMG 23988T (96.7 %, sequence similarity), Pontirhabdus pectinovorans JC2675T (96.3 %), Postechiella marina M091T (95.6 %) and Hyunsoonleella jejuensis CNU004T (95.3 %). The 16S rRNA gene sequence similarity (98.8 %) and DNA-DNA relatedness (78.1 %) between strains KYW371T and KS18 indicated that these two strains represented a single species. The predominant cellular fatty acids of strain KYW371T were iso-C15:1 G (22.8 %), iso-C15:0 (20.1 %), iso-C15:0 3-OH (15.2 %) and iso-C17:0 3-OH (13.2 %). Flexirubin-type pigments were absent. MK-6 was the only isoprenoid quinone and the DNA G+C content was 34.8-36.6 mol%. Data from a polyphasic taxonomy study suggested that the isolates represent a novel genus and species in the family Flavobacteriaceae, for which the name Marinivirga aestuarii gen. nov., sp. nov. is proposed. The type strain is KYW371T (=KCTC 23449T =JCM 17452T). Emended descriptions of the genera Hyunsoonleella, Jejuia and Pontirhabdus and Hyunsoonleella jejuensis, Jejuia pallidilutea and Pontirhabdus pectinivorans are also proposed.
INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY 08/2012; · 2.11 Impact Factor
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ABSTRACT: The aim of this study was to evaluate the antioxidant properties of an edible lichen Ramalina conduplicans. The extract exhibited potent anti-linoleic acid peroxidation activity, free radical-scavenging activity, and reducing power.
The total phenolic contents were found to be high in the extract. Activity-guided bioautographic thin layer chromatography
(TLC) and HPLC identified sekikaic acid and homosekikaic acid as the main free radical-scavenging compounds in R. conduplicans extract (IC50 [50% inhibition concentration]=0.082 and 0.276mg/ml, respectively). The results suggested that this edible lichen species
have the potential to be utilized as food additives or as protective drugs.
KeywordsBioautographic TLC-Homosekikaic acid-In vitro-Sekikaic acid-Total phenolic contents
Mycoscience 04/2012; 51(5):391-395. · 1.21 Impact Factor
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ABSTRACT: Eight lichen species, Cetraria aculeata, Cladonia furcata, Pseudephebe pubescens, Sphaerophorus globosus, Stereocaulon alpinum, Umbilicaria antarctica, Usnea antarctica and Usnea aurantiacoatra, were collected from King George Island, maritime Antarctica, for the evaluation of antioxidant activities. Anti-linoleic
acid peroxidation activity, free radical scavenging activity, reducing power and superoxide anion scavenging activity were
assessed of methanol and acetone extract of the lichens invitro. Extract of Umbilicaria antarctica, Cladonia furcata, Sphaerophorus globosus and Usnea antarctica were found to have strong invitro antioxidant properties. In general, acetone extract exhibited stronger activities than
methanol extract. The activity-guided bioautographic TLC and HPLC analysis demonstrated that lecanoric acid was the main antioxidant
compound in the acetone extract of Umbilicaria antarctica, the most potent antioxidant lichen species among the test species. The results suggested that several Antarctic lichens and their substances can be used as novel bioresources of natural antioxidants.
Polar Biology 04/2012; 32(7):1033-1040. · 1.66 Impact Factor
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ABSTRACT: A strictly aerobic, orange-pigmented and Gram-staining-negative bacterium, designated K17-16(T), was isolated from seawater of Gangjin Bay, Korea. Comparative 16S rRNA gene sequence analysis revealed that strain K17-16(T) was a member of the genus Polaribacter in the family Flavobacteriaceae and showed 94.0-95.6 % sequence similarity with the type strains of recognized species of the genus Polaribacter. The G+C content of the genomic DNA was 34.6 mol% and the major respiratory lipoquinone was MK-6. The major polar lipids detected were phosphatidylethanolamine, three unidentified amino-group-containing lipids and an unidentified aminophospholipid. The predominant cellular fatty acids were iso-C(15 : 0) (15.4 %), C(15 : 0) (12.4 %), summed feature 3 (comprising iso-C(15 : 0) 2-OH and/or C(16 : 1)ω7c; 10.6 %), C(15 : 1)ω6c (9.8 %) and iso-C(15 : 0) 3-OH (8.6 %). On the basis of phenotypic and genotypic data, strain K17-16(T) represents a novel species in the genus Polaribacter, for which the name Polaribacter gangjinensis sp. nov. is proposed. The type strain is K17-16(T) ( = KCTC 22729(T) = JCM 16152(T)).
INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY 06/2011; 61(Pt 6):1425-9. · 2.11 Impact Factor
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ABSTRACT: The present study was conducted to evaluate the antibacterial activity of lichen-forming fungi (LFF) against Helicobacter pylori, and to optimize the culture conditions of LFF for maximum production of natural antibiotics against H. pylori. To accomplish this, a screening assay was first conducted among 19 species of LFF. The extract of Nephromopsis pallescens (KOLRI-040516) exhibited the strongest anti-ff. pylori activity. Bioautograghic TLC and HPLC analysis identified usnic acid as the main antibacterial substance produced by JV. pallescens. The growth of JV. pallescens and production of antibacterial substances produced by the fungus were then investigated under several culture conditions including the culture media, initial medium pHs, incubation temperatures, and the degree of aeration. The results indicated that culture in MY medium with an initial pH of 6.0, a temperature of 15°C and a low degree of aeration supported the largest usnic acid production of the fungus (16.4 ug usnic acid/g dry biomass). Especially, aeration was found to be an important factor that affect both growth and usnic acid production of N. pallescens.
The Journal of Microbiology 02/2011; 49(1):66-70. · 1.10 Impact Factor
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ABSTRACT: Antioxidant properties of 46 lichen species collected from high-UV exposed alpine areas of southwestern China were evaluated for their therapeutic utilization. Anti-linoleic acid peroxidation activity, 1, 1-diphenyl-2-picryl-hydrazyl (DPPH) scavenging activity, reducing power and the total phenolic contents were assessed in methanol extract of the lichens in vitro. Extracts of Peltigera praetextata and Sticta nylanderiana exhibited potent activity in all antioxidant tests. Especially, extracts of S. nylanderiana exhibited 1.37 times higher anti-linoleic acid peroxidation activity than ascorbic acid used as a positive control. It also showed the strongest free radical scavenging activity among all the tested species with an inhibition of 90.4% at the concentration of 330microgram/ml. Potent reducing power was also detected in the lichen extract compared with BHA. Generally, the antioxidant lichens contained large amount of phenolic contents. The activity-guided bioautographic TLC and HPLC analysis are used to find out the compounds responsible for the potent antioxidant activities of S. nylanderiana extract. The analysis demonstrated that lecanoric acid is one of the effective antioxidant compounds in S. nylanderiana. The results suggested that several highland lichens can be used as a novel bioresource for natural antioxidants.
Journal of Microbiology and Biotechnology 11/2010; 20(11):1524-8. · 1.38 Impact Factor
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ABSTRACT: Efficient control of Xanthomonas arboricola pv. pruni, the causal agent of bacterial spot on stone fruit, requires a sensitive and reliable diagnostic tool. A PCR detection method that utilizes primers to target the hrp gene cluster region was developed in this study. The nucleotide sequence of the PCR product amplified with primers specific for the hrp region of the xanthomonads and genomic DNA of X. arboricola pv. pruni was determined, and the sequence was aligned with that of X. campestris pv. campestris, which was obtained from the GenBank database. On the basis of the sequence of the amplified hrp region, a PCR primer set of XapF/R specific to X. arboricola pv. pruni was designed. This primer set yielded a 243-bp product from the genomic DNA of X. aboricola pv. pruni strains, but no products from other 21 strains of Xanthomonas or from two epiphytic bacterial species. Southern blot hybridization with the probe derived from the PCR product with the primer set and X. aboricola pv. pruni DNA confirmed the PCR results. The Xap primer system was successfully applied to detect the pathogen from infected peach fruits. When it was applied in field samples, the primer set was proved as a reliable diagnostic tool for specific detection of X. aboricola pv. pruni from peach orchards.
The Journal of Microbiology 10/2010; 48(5):554-8. · 1.10 Impact Factor
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ABSTRACT: A strictly aerobic, red-pigmented, non-motile, catalase- and oxidase-positive, Gram-staining-negative bacterium, designated strain CNURIC011(T), was isolated from seawater off the coast of Jeju Island in Korea. A phylogenetic analysis based on 16S rRNA gene sequences showed that strain CNURIC011(T) 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 23177(T), Aquimarina marcrocephali JAMB N27(T), Aquimarina intermedia KMM 6258(T), Aquimarina muelleri KMM 6020(T), and Aquimarina brevivitae SMK-19(T), 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 CNURIC011(T) and Aquimarina latercula ATCC 23177(T) (=KCTC 2912(T)) 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-C(15:0) (14.9%), C(15:0) (13.9%), iso-C(17:0) 3-OH (12.6%), iso-C(15:1) G (7.3%), and iso-C(17:1) omega9c (7.2%). On the basis of phenotypic, phylogenetic, and genotypic data, strain CNURIC011(T) represents a novel species within the genus Aquimarina, for which the name Aquimarina litoralis sp. nov. is proposed. The type strain is CNURIC011(T) (=KCTC 22614(T) =JCM 15974(T)).
The Journal of Microbiology 08/2010; 48(4):433-7. · 1.10 Impact Factor
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ABSTRACT: A novel strictly aerobic, orange-pigmented, Gram-stain-negative bacterium, designated strain GJ16(T), was isolated from coastal seawater of Gangjin Bay, the southernmost part of the Korean peninsula, and subjected to a polyphasic taxonomic study. It grew optimally at 25-30 °C, at pH 7.0-8.0 and in the presence of 3 % NaCl. Comparative 16S rRNA gene sequence analysis revealed that strain GJ16(T) formed a distinct lineage within the family Flavobacteriaceae and shared less than 91.2 % 16S rRNA gene sequence similarity with members of the genera Leptobacterium, Zhouia, Winogradskyella, Dokdonia and Krokinobacter. The predominant cellular fatty acids were iso-C(15 : 0) (40.2 %), iso-C(15 : 1) G (12.8 %), iso-C(17 : 0) 3-OH (11.2 %) and C(15 : 0) (6.6 %). The G+C content of the genomic DNA was 39.4 mol% and the major respiratory isoprenoid quinone was MK-6. On the basis of phenotypic and genotypic data, strain GJ16(T) represents a novel species in a new genus in the family Flavobacteriaceae, for which the name Gangjinia marincola gen. nov., sp. nov. is proposed; the type strain is GJ16(T) (=KCTC 22649(T) =JCM 16082(T)).
INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY 03/2010; 61(Pt 2):325-9. · 2.11 Impact Factor
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ABSTRACT: A novel Gram-negative, aerobic, orange-pigmented bacterial strain, designated K7-2(T), was isolated from seawater of Gangjin Bay, Korea, and subjected to a polyphasic taxonomic study. Strain K7-2(T) contained ubiquinone-10 (Q-10) as the predominant respiratory lipoquinone and did not produce bacteriochlorophyll a. Major fatty acids were C(18 : 1)omega7c (51.4 %), iso-C(15 : 0) 2-OH and/or C(16 : 1)omega7c (15.0 %) and C(17 : 1)omega6c (8.8 %). Major polar lipids were phosphatidylethanolamine and phosphatidylcholine. The DNA G+C content was 61.6 mol%. Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain K7-2(T) formed a distinct phylogenetic lineage within the cluster comprising Erythrobacter strains. Similarities between the 16S rRNA gene sequences of strain K7-2(T) and the type strains of Erythrobacter species ranged from 95.0 % (Erythrobacter litoralis DSM 8509(T)) to 96.8 % (Erythrobacter citreus RE35F/1(T)). On the basis of polyphasic taxonomic data, strain K7-2(T) (=KCTC 22330(T)=JCM 15420(T)) is classified in a novel species within the genus Erythrobacter, for which the name Erythrobacter gangjinensis sp. nov. is proposed.
International journal of systematic and evolutionary microbiology 09/2009; 60(Pt 6):1413-7. · 2.27 Impact Factor
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ABSTRACT: A novel, strictly aerobic, Gram-stain-negative, yellow-orange-pigmented, rod-shaped bacterium was isolated from abalone (Haliotis discus) under aquaculture in seawater off the Wando coast, Southern Korea, and subjected to a polyphasic taxonomic study. Cells of strain Haldis-1(T) were catalase- and oxidase-positive rods with flexirubin pigments. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain Haldis-1(T) formed a distinct lineage within the family Cryomorphaceae and could be distinguished from the related genera Lishizhenia and Fluviicola. Strain Haldis-1(T) shared 16S rRNA gene sequence similarities of 92.5 and 92.4 % with Lishizhenia caseinilytica UST040201-001(T) and Fluviicola taffensis RW262(T), respectively. The DNA G+C content was 38.1 mol% and the major respiratory quinone was MK-7. The predominant cellular fatty acids were iso-C(15 : 0) (38.6 %), C(15 : 0) 2-OH (20.3 %) and C(15 : 0) (10.7 %). Growth was observed at 25-42 degrees C (optimum 30-37 degrees C) and at pH 6.5-9.5 (optimum pH 6.5-8.0). On the basis of polyphasic analysis of phenotypic, genotypic and phylogenetic data, strain Haldis-1(T) represents a novel genus and species within the family Cryomorphaceae in the phylum Bacteroidetes, for which the name Wandonia haliotis gen. nov., sp. nov. is proposed. The type strain is Haldis-1(T) (=KCTC 22610(T) =NBRC 105642(T)).
International journal of systematic and evolutionary microbiology 09/2009; 60(Pt 3):510-4. · 2.27 Impact Factor
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ABSTRACT: An aerobic, pale-orange-pigmented, Gram-stain-negative bacterium, designated strain EM39T, was isolated from seawater from the eastern coast of Jeju Island, Korea, and its taxonomic status was established using a polyphasic approach. Comparative 16S rRNA gene sequence studies revealed that strain EM39T formed a distinct lineage within the family Flavobacteriaceae and could be distinguished from strains of members of the related genera Gaetbulibacter, Mariniflexile and Tamlana by 16S rRNA gene sequence analysis (similarity values between strain EM39T and related strains were all less than 93.8%). Cells of strain EM39T were non-gliding, catalase- and oxidase-positive rods that were devoid of flexirubin pigments. Growth was observed at 15-35 degrees C (optimum, 25-30 degrees C) and pH 6.5-9.0 (optimum, pH 7.0-8.5). The genomic DNA G+C content was 34.6 mol% and the major respiratory quinone was MK-6. The predominant cellular fatty acids were iso-C15:0, iso-C15:1 G and iso-C17:0 3-OH. On the basis of phenotypic and genotypic data, strain EM39T represents a novel species in a new genus in the family Flavobacteriaceae, for which the name Jejuia pallidilutea gen. nov., sp. nov. is proposed. The type strain is EM39T (=KCTC 22298T=DSM 21165T).
International journal of systematic and evolutionary microbiology 08/2009; 59(Pt 9):2148-52. · 2.27 Impact Factor
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ABSTRACT: A rod-shaped, yellow-pigmented, aerobic, Gram-negative bacterium, designated strain JO-1(T), was isolated from an apparently healthy Pacific oyster, Crassostrea gigas, collected at Wan Island, Korea. It grew at 15-37 degrees C (optimum 30 degrees C) only in the presence of sea salts. Strain JO-1(T) hydrolysed casein, Tween 80 and starch. The major fatty acids were iso-C(15 : 0) (23.8 %), summed feature 3 (comprising C(16 : 1)omega7c and/or iso-C(15 : 0) 2-OH; 14.5 %) and iso-C(15 : 1) G (14.1 %). Analysis of the 16S rRNA gene sequence indicated that strain JO-1(T) was a member of the genus Tenacibaculum in the family Flavobacteriaceae, with sequence similarity of 94.6-97.8 % to the type strains of recognized members of the genus. The G+C content of the genomic DNA was 31.4 mol%. DNA-DNA relatedness levels between strain JO-1(T) and the five closest relatives, Tenacibaculum litoreum KCCM 42115(T), T. lutimaris KCTC 12302(T), T. aestuarii KCTC 12569(T), T. mesophilum DSM 13764(T) and T. adriaticum JCM 14633(T), were less than 28 %. Phylogenetic analyses and differences in physiological and biochemical characteristics suggested that strain JO-1(T) (=KCTC 22329(T) =JCM 15428(T)) should be classified as the type strain of a novel species within the genus Tenacibaculum, for which the name Tenacibaculum crassostreae sp. nov. is proposed.
International journal of systematic and evolutionary microbiology 07/2009; 59(Pt 7):1609-14. · 2.27 Impact Factor
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ABSTRACT: An aerobic, gliding, yellow-pigmented bacterium lacking flagella and showing strong tyrosinase activity, designated strain EM41(T), was isolated from seawater on the eastern coast of Jeju Island in Korea. Growth was observed at 15-35 degrees C (optimum, 25-30 degrees C) and at pH 6.5-9.0 (optimum, pH 7.0-8.5). Cells were Gram-negative, negative for flexirubin pigments and catalase- and oxidase-positive. The G+C content of the genomic DNA was 33.5 mol% and the major respiratory quinone was menaquinone-6 (MK-6). Comparative 16S rRNA gene sequence analysis showed that strain EM41(T) formed a distinct phyletic line within the genus Cellulophaga with a 100 % bootstrap value and was most closely related to Cellulophaga pacifica KMM 3664(T) (97.0 % sequence similarity). The level of DNA-DNA relatedness between strain EM41(T) and C. pacifica KMM 3664(T) was about 17.8 %. On the basis of phenotypic and genotypic data, strain EM41(T) is considered to represent a novel species of the genus Cellulophaga, for which the name Cellulophaga tyrosinoxydans sp. nov. is proposed. The type strain is EM41(T) (=KCTC 22297(T)=DSM 21164(T)).
International journal of systematic and evolutionary microbiology 05/2009; 59(Pt 4):654-7. · 2.27 Impact Factor
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ABSTRACT: A gene encoding an alkaline (pI of 8.67) chitinase was cloned and sequenced from Chromobacterium sp. strain C-61. The gene was composed of 1,611 nucleotides and encoded a signal sequence of 26 N-terminal amino acids and a mature protein of 510 amino acids. Two chitinases of 54 and 52 kDa from both recombinant Escherichia coli and C-61 were detected on SDS-PAGE. Maximum chitinase activity was obtained in the culture supernatant of recombinant E. coli when cultivated in TB medium for 6 days at 37 degrees C and was about fourfold higher than that from C-61. Chi54 from the culture supernatants could be purified by a single step based on isoelectric point. The purified Chi54 had about twofold higher binding affinity to chitin than to cellulose. The chi54 encoded a protein that included a type 3 chitin-binding domain belonging to group A and a family 18 catalytic domain belonging to subfamily A. In the catalytic domain, mutation of perfectly conserved residues and highly conserved residues resulted in loss of nearly all activity, while mutation of nonconserved residues resulted in enzymes that retained activity. In this process, a mutant (T218S) was obtained that had about 133% of the activity of the wild type, based on comparison of K (cat) values.
Applied Microbiology and Biotechnology 04/2007; 74(4):791-804. · 3.42 Impact Factor
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ABSTRACT: Fifty-six species in 36 genera of macrolichens are reported from the Zhongdian area, northwest Yunnan, China during the lichenological expedition for highland macrolichen survey in June, 2004. More than 60% of these species have not been reported in South Korea. All of the 182 collected specimens are deposited in the Korean Lichen Research Institute (KoLRI) at Sunchon National University in Korea, and some of them are duplicated in the lichen herbarium, Crytogamic Herbarium, Kunming Institute of Botany, Academia Sinica (KUN-L) in China. This is the first report on the macrolichen flora in the visited areas.
The Journal of Microbiology 07/2005; 43(3):228-36. · 1.10 Impact Factor
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ABSTRACT: The occurrence of strA-strB streptomycin-resistance genes within transposon Tn5393 was examined in Pseudomonas syringae pv. actinidiae, P. syringae pv. syringae, and P. marginalis, isolated from kiwifruit plants in Korea and Japan. PCR amplification with primers specific to strA-strB revealed that three of the tested Pseudomonas species harbored these genes for a streptomycin-resistance determinant. Tn5393, containing strA-strB, was also identified with PCR primers designed to amplify parts of tnpA, res, and tnpR. No IS elements were detected within tnpR, nor were they found in the intergenic region between tnpR and strA. Nucleotide sequence analysis indicated that the strA sequence of P. syringae pv. actinidiae contained a single nucleotide alteration at position 593 (CAA-->CGA), as compared to Tn5393a in P. syringae pv. syringae. This resulted in an amino acid change, from Gln to Arg.
The Journal of Microbiology 12/2004; 42(4):365-8. · 1.10 Impact Factor
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ABSTRACT: 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.
The Journal of Microbiology 07/2004; 42(2):163-7. · 1.10 Impact Factor
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ABSTRACT: A xylanase gene, xynX, of Clostridium thermocellum had one thermostabilizing domain (TSD) between the signal peptide sequence and the catalytic domain (CD). The TSD of a truncated xylanase gene, xynX'(TSD-CD), was transpositioned from the N terminus to the C terminus of the CD by overlapping PCRs, and a modified product, xynX'(CD-TSD), was constructed. XynX'(TSD-CD) had a higher optimum temperature (70 degrees C versus 65 degrees C) and was more thermostable (residual activity of 68% versus 46% after a 20-min preincubation at 70 degrees C) than the one without the TSD, XynX'(CD). However, the domain-transpositioned enzyme, XynX'(CD-TSD), showed a lower optimum temperature (30 degrees C) and thermostability (20%) than XynX'(CD). Both XynX'(TSD-CD) and XynX'(CD-TSD) showed significantly higher binding capacity toward xylan than XynX'(CD), and the domain transposition did not cause any change in the binding ability. XynX'(TSD-CD) and XynX'(CD-TSD) also showed considerable binding to lichenan but not to carboxymethyl cellulose and laminarin. XynX'(TSD-CD) and XynX'(CD-TSD) had higher activities for insoluble xylan than XynX'(CD), while XynX'(CD) was more active against soluble xylan than XynX'(TSD-CD) and XynX'(CD-TSD). These results indicate that the TSD of XynX has dual functions, xylan binding and thermostabilization, and the domain should also be classified as a xylan-binding domain (XBD). The binding capacity of the XBD was not affected by domain transpositioning within the gene.
Applied and Environmental Microbiology 08/2002; 68(7):3496-501. · 3.83 Impact Factor
