- Volume 50(1); February 2012
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Review
- REVIEW] Recent Findings about the Yersinia enterocolitica Phage Shock Protein Response
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Saori Yamaguchi , Andrew J. Darwin
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J. Microbiol. 2012;50(1):1-7. Published online February 27, 2012
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DOI: https://doi.org/10.1007/s12275-012-1578-7
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Abstract
- The phage shock protein (Psp) system is a conserved extracytoplasmic
stress response in bacteria that is essential
for virulence of the human pathogen Yersinia enterocolitica.
This article summarizes some recent findings about Y. enterocolitica
Psp system function. Increased psp gene expression
requires the transcription factor PspF, but under
non-inducing conditions PspF is inhibited by an interaction
with another protein, PspA, in the cytoplasm. A Psp-inducing
stimulus causes PspA to relocate to the cytoplasmic
membrane, freeing PspF to induce psp gene expression.
This PspA relocation requires the integral cytoplasmic
membrane proteins, PspB and PspC, which might sense an
inducing trigger and sequester PspA by direct interaction.
The subsequent induction of psp gene expression increases
the PspA concentration, which also allows it to contact the
membrane directly, perhaps for its physiological function.
Mutational analysis of the PspB and PspC proteins has revealed
that they both positively and negatively regulate psp
gene expression and has also identified PspC domains associated
with each function. We also compare the contrasting
physiological roles of the Psp system in the virulence of Y.
enterocolitica and Salmonella enterica sv. Typhimurium (S.
Typhimurium). In S. Typhimurium, PspA maintains the
proton motive force, which provides the energy needed to
drive ion importers required for survival within macrophages.
In contrast, in the extracellular pathogen Y. enterocolitica,
PspB and PspC, but not PspA, are the Psp components
needed for virulence. PspBC protect Y. enterocolitica from
damage caused by the secretin component of its type 3 secretion
system, an essential virulence factor.
Research Support, Non-U.S. Gov'ts
- Stratified Distribution of Nutrients and Extremophile Biota within Freshwater Ice Covering the Surface of Lake Baikal
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Nina A. Bondarenko , Olga I. Belykh , Ludmila P. Golobokova , Olga V. Artemyeva , Natalia F. Logacheva , Irina V. Tikhonova , Irina A. Lipko , Tatyana Ya. Kostornova , Valentina V. Parfenova , Tamara V. Khodzher , Young-Gun Zo
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J. Microbiol. 2012;50(1):8-16. Published online February 27, 2012
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DOI: https://doi.org/10.1007/s12275-012-1251-1
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Abstract
- Biological entities and gradients of selected chemicals within
the seemingly barren ice layers covering Lake Baikal were
investigated. Ice cores 40–68 cm long were obtained from
inshore and offshore sites of Southern Lake Baikal during
the cold period of a year (March-April) in 2007 and 2008.
In microscopic observations of the melted ice, both algae
and bacteria were found in considerable numbers (>103
cells/L and >104 cells/ml, respectively). Among all organisms
found, diatom was generally the most predominant taxon
in the ice. Interestingly, both planktonic and benthic algae
were present in considerable numbers (2–4×104 cells/L).
Dominant phototrophic picoplankton were comprised of
small green algae of various taxa and cyanobacteria of
Synechococcus and Cyanobium. The bacterial community
consisted mostly of short rod and cocci cells, either freeliving
or aggregated. Large numbers of yeast-like cells and
actinomycete mycelium were also observed. Concentrations
of silica, phosphorus, and nitrate were low by an order of
magnitude where biota was abundant. The profile of the ice
could be interpreted as vertical stratification of nutrients and
biomass due to biological activities. Therefore, the organisms
in the ice were regarded to maintain high activity while
thriving under freezing conditions. Based on the results, it
was concluded that the freshwater ice covering the surface
of Lake Baikal is considerably populated by extremophilic
microorganisms that actively metabolize and form a detritus
food chain in the unique large freshwater ecosystem of
Lake Baikal.
- Effects of Phosphate Addition on Biofilm Bacterial Communities and Water Quality in Annular Reactors Equipped with Stainless Steel and Ductile Cast Iron Pipes
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Hyun-Jung Jang , Young-June Choi , Hee-Myong Ro , Jong-Ok Ka
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J. Microbiol. 2012;50(1):17-28. Published online February 27, 2012
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DOI: https://doi.org/10.1007/s12275-012-1040-x
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34
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Abstract
- The impact of orthophosphate addition on biofilm formation
and water quality was studied in corrosion-resistant
stainless steel (STS) pipe and corrosion-susceptible ductile cast
iron (DCI) pipe using cultivation and culture-independent
approaches. Sample coupons of DCI pipe and STS pipe
were installed in annular reactors, which were operated for
9 months under hydraulic conditions similar to a domestic
plumbing system. Addition of 5 mg/L of phosphate to the
plumbing systems, under low residual chlorine conditions,
promoted a more significant growth of biofilm and led to a
greater rate reduction of disinfection by-products in DCI pipe
than in STS pipe. While the level of THMs (trihalomethanes)
increased under conditions of low biofilm concentration,
the levels of HAAs (halo acetic acids) and CH (chloral hydrate)
decreased in all cases in proportion to the amount of
biofilm. It was also observed that chloroform, the main species
of THM, was not readily decomposed biologically and
decomposition was not proportional to the biofilm concentration;
however, it was easily biodegraded after the addition
of phosphate. Analysis of the 16S rDNA sequences of 102
biofilm isolates revealed that Proteobacteria (50%) was the
most frequently detected phylum, followed by Firmicutes
(10%) and Actinobacteria (2%), with 37% of the bacteria
unclassified. Bradyrhizobium was the dominant genus on
corroded DCI pipe, while Sphingomonas was predominant
on non-corroded STS pipe. Methylobacterium and Afipia
were detected only in the reactor without added phosphate.
PCR-DGGE analysis showed that the diversity of species in
biofilm tended to increase when phosphate was added regardless
of the pipe material, indicating that phosphate addition
upset the biological stability in the plumbing systems.
- Host Species as a Strong Determinant of the Intestinal Microbiota of Fish Larvae
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Xuemei Li , Yuhe Yu , Weisong Feng , Qingyun Yan , Yingchun Gong
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J. Microbiol. 2012;50(1):29-37. Published online February 27, 2012
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DOI: https://doi.org/10.1007/s12275-012-1340-1
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118
Citations
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Abstract
- We investigated the influence of host species on intestinal
microbiota by comparing the gut bacterial community structure
of four cohabitating freshwater fish larvae, silver carp,
grass carp, bighead carp, and blunt snout bream, using denaturing
gradient gel electrophoresis (DGGE) of the amplified
16S and 18S rRNA genes. Similarity clustering indicated
that the intestinal microbiota derived from these four fish
species could be divided into four groups based on 16S
rRNA gene similarity, whereas the eukaryotic 18S rRNA
genes showed no distinct groups. The water sample from the
shared environment contained microbiota of an independent
group as indicated by both 16S and 18S rRNA genes segments.
The bacterial community structures were visualized using
rank-abundance plots fitted with linear regression models.
Results
showed that the intestinal bacterial evenness was
significantly different between species (P<0.05) and between
species and the water sample (P<0.01). Thirty-five relatively
dominant bands in DGGE patterns were sequenced and
grouped into five major taxa: Proteobacteria (26), Actinobacteria
(5), Bacteroidetes (1), Firmicutes (2), and Cyanobacterial
(1). Six eukaryotes were detected by sequencing 18S rRNA
genes segments. The present study suggests that the intestines
of the four fish larvae, although reared in the same environment,
contained distinct bacterial populations, while intestinal
eukaryotic microorganisms were almost identical.
- Gram-positive Rhizobacterium Bacillus amyloliquefaciens FZB42 Colonizes Three Types of Plants in Different Patterns
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Ben Fan , Rainer Borriss , Wilfrid Bleiss , Xiaoqin Wu
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J. Microbiol. 2012;50(1):38-44. Published online February 27, 2012
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DOI: https://doi.org/10.1007/s12275-012-1439-4
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Abstract
- The colonization of three types of different plants, Zea mays,
Arabidopsis thaliana, and Lemna minor, by GFP-labeled
Gram-positive rhizobacterium Bacillus amyloliquefaciens
FZB42 was studied in gnotobiotic systems using confocal
laser scanning microscopy and electron microscopy. It was
demonstrated that FZB42 was able to colonize all the plants.
On one hand, similar to some Gram-negative rhizobacteria
like Pseudomonas, FZB42 favored the areas such as the
concavities in root surfaces and the junctions where lateral
roots occurred from the primary roots; on the other hand, we
clearly demonstrated that root hairs were a popular habitat
to the Gram-positive rhizobacterium. FZB42 exhibited a
specific colonization pattern on each of the three types of
plants. On Arabidopsis, tips of primary roots were favored by
FZB42 but not so on maize. On Lemna, FZB42 accumulated
preferably along the grooves between epidermal cells of
roots and in the concave spaces on ventral sides of fronds.
The results suggested L. minor to be a promising tool for
investigations on plant-microbial interaction due to a series
of advantages it has. Colonization of maize and Arabidopsis
roots by FZB42 was also studied in the soil system. Comparatively,
higher amount of FZB42 inoculum (~108 CFU/ml)
was required for detectable root colonization in the soil
system, where the preference of FZB42 cells to root hairs
were also observed.
- Growth Promotion of Xanthium italicum by Application of Rhizobacterial Isolates of Bacillus aryabhattai in Microcosm Soil
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Sol Lee , Jong-Ok Ka , Hong-Gyu Song
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J. Microbiol. 2012;50(1):45-49. Published online February 27, 2012
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DOI: https://doi.org/10.1007/s12275-012-1415-z
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63
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Abstract
- This study was conducted using rhizobacteria, which are
able to exert beneficial effects upon plant growth in the infertile
soil collected from barren lakeside areas. Four strains
of plant growth promoting bacteria were isolated from the
rhizosphere of a common wild plant, Erigeron canadensis.
Isolated strains LS9, LS11, LS12, and LS15 were identified
as Bacillus aryabhattai by 16S rDNA sequence analysis. B.
aryabhattai LS9, LS11, LS12, and LS15 could solubilize
577.9, 676.8, 623.6, and 581.3 mg/L of 0.5% insoluble calcium
phosphate within 2 days of incubation. Production of indole
acetic acid, a typical growth promoting phytohormone
auxin, by strain LS15 was 471.3 mg/L in 2 days with the addition
of auxin precursor L-tryptophan. All the strains also
produced other phytohormones such as indole butyric acid,
gibberellins, and abscisic acid, and strain LS15 showed the
highest production rate of gibberellin (GA3), 119.0 μg/mg
protein. Isolated bacteria were used in a microcosm test for
growth of wild plant Xanthium italicum, which can be utilized
as a pioneer plant in barren lands. Seed germination
was facilitated, and the lengths of roots, and shoots and the
dry weights of germinated seedlings after 16 days were
higher than those of the uninoculated control plants. Root
lengths of seedlings of X. italicum increased by 121.1% in
LS11-treated samples after 16 days. This plant growth-promoting
capability of B. aryabhattai strains may be utilized
as an environmentally friendly means of revegetating barren
lands, especially sensitive areas such as lakeside lands.
- Diversity and Physiological Properties of Root Endophytic Actinobacteria in Native Herbaceous Plants of Korea
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Tae-Ui Kim , Sung-Heun Cho , Ji-Hye Han , Young Min Shin , Hyang Burm Lee , Seung Bum Kim
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J. Microbiol. 2012;50(1):50-57. Published online February 27, 2012
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DOI: https://doi.org/10.1007/s12275-012-1417-x
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Abstract
- Endophytic actinobacterial diversity in the native herbaceous
plant species of Korea was analyzed using a culturebased
approach. Sixty one actinobacterial strains were isolated,
and assigned to 15 genera based on 16S rRNA gene
analysis. The members of the genus Streptomyces comprised
45.9% of the total isolates, followed by Micromonospora
(18.8%), Rhodococcus (6.6%), Microbispora (4.9%), and
Micrococcus (4.9%). Other minor constituents included
members of Microbacterium, Streptacidiphilus, Arthrobacter,
Dietzia, Kitasatospora, Herbiconiux, Mycobacterium, Nocardia,
Rathayibacter, and Tsukamurella. Among the isolates, 65.6%
exhibited at least one hydrolytic enzyme activity out of four,
and 45.9% exhibited antagonistic activity against at least
one fungal pathogen out of five, thus demonstrating that
endophytic actinobacteria can be an important source of
bioactive compounds. Notably, most strains of Streptomyces
proved active for both enzymatic and antagonistic activities.
- Microflora Profiling of Infected Root Canal before and after Treatment Using Culture-Independent Methods
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Yasuhiro Ito , Takuichi Sato , Keiko Yamaki , Gen Mayanagi , Kazuhiro Hashimoto , Hidetoshi Shimauchi , Nobuhiro Takahashi
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J. Microbiol. 2012;50(1):58-62. Published online February 27, 2012
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DOI: https://doi.org/10.1007/s12275-012-0459-4
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Abstract
- This study aimed to profile the microflora in infected root
canals before and after root canal treatment using cultureindependent
methods
. Six infected root canals in singlerooted
teeth with periapical lesions from five subjects were
included. Quantification of total bacteria was performed by
real-time PCR with primers targeting 16S rRNA genes.
PCR products with universal 16S rRNA gene primers were
cloned and partially sequenced, and bacterial identification
at the species level was performed by comparative analysis
with the GenBank database. The concentration of extracted
DNA before treatment was higher than that after root canal
treatment, although the difference was not statistically
significant. Sequence analysis revealed that oral bacteria
such as Fusobacterium, Streptococcus, Olsenella, and Pseudoramibacter
detected in cases before root canal treatment
disappeared after treatment. These results suggest that the
root canal microflora are distinct before and after root
canal treatment, and that treatment changes the microflora
in both quantity and quality.
- Phenotypic and Phylogenetic Analysis of Lactic Acid Bacteria Isolated from Forage Crops and Grasses in the Tibetan Plateau
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Huili Pang , Zhongfang Tan , Guangyong Qin , Yanping Wang , Zongwei Li , Qingsheng Jin , Yimin Cai
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J. Microbiol. 2012;50(1):63-71. Published online February 27, 2012
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DOI: https://doi.org/10.1007/s12275-012-1284-5
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Abstract
- A total of 140 lactic acid bacteria (LAB) strains were isolated
from corn, alfalfa, clover, sainfoin, and Indian goosegrass
in the Tibetan Plateau. According to phenotypic and chemotaxonomic
characteristics, 16S rDNA sequence, and recA
gene PCR amplification, these LAB isolates were identified
as belonging to five genera and nine species. Corn contained
more LAB species than other forage crops. Leuconostoc
pseudomesenteroides, Lactococcus lactis subsp. lactis, Lactobacillus
brevis, and Weissella paramesenteroides were dominant
members of the LAB population on alfalfa, clover, sainfoin,
and Indian goosegrass, respectively. The comprehensive
16S rDNA and recA-based approach effectively described
the LAB community structure of the relatively abundant LAB
species distributed on different forage crops. This is the
first report describing the diversity and natural populations
of LAB associated with Tibetan forage crops, and most isolates
grow well at or below 10°C. The results will be valuable for
the future design of appropriate inoculants for silage fermentation
in this very cold area.
Journal Article
- Purification and Characterization of a Novel Laccase from the Edible Mushroom Hericium coralloides
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Ya-Jie Zou , He-Xiang Wang , Tzi-Bun Ng , Chen-Yang Huang , Jin-Xia Zhang
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J. Microbiol. 2012;50(1):72-78. Published online February 27, 2012
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DOI: https://doi.org/10.1007/s12275-012-1372-6
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Abstract
- A novel laccase from the edible mushroom Hericium coralloides
was purified by ion exchange chromatography on
diethylaminoethyl (DEAE) cellulose, carboxymethyl (CM)
cellulose, and Q-Sepharose columns followed by fast protein
liquid chromatography gel filtration on a Superdex 75
column. Analysis by gel filtration and SDS-PAGE indicated
that the protein is a monomer in solution with a molecular
mass of 65 kDa. Its N-terminal amino acid sequence was
AVGDDTPQLY, which exhibits partial sequence homology
to previously isolated laccases. Optimum activity was observed
at pH 2.2 and at 40°C. The enzyme showed activity
toward a variety of substrates, the most sensitive of which
was 2,2-azinobis [3-ethylbenzothiazolone-6-sulfonic acid]
diammonium salt (ABTS). The degradation activity toward
substrates was ABTS > N,N-dimethyl-1,4-phenylenediamine
> catechol > 2-methylcatechol > pyrogallol. The laccase did
not exert any antiproliferative activity against Hep G2 or
MCF 7 tumor cell lines at a concentration of 60 μM, unlike
some previously reported mushroom proteins, but showed
significant activity toward human immunodeficiency virus-1
(HIV-1) reverse transcriptase with an IC50 of 0.06 μM.
Research Support, Non-U.S. Gov'ts
- The PseEF Efflux System Is a Virulence Factor of Pseudomonas syringae pv. syringae
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Hyosun Cho , Hyojeung Kang
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J. Microbiol. 2012;50(1):79-90. Published online February 27, 2012
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DOI: https://doi.org/10.1007/s12275-012-1353-9
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Abstract
- An ATP-binding cassette (ABC) transporter, called the PseEF
efflux system, was identified at the left border of the syr-syp
genomic island of Pseudomonas syringae pv. syringae strain
B301D. The PseEF efflux system was located within a 3.3-kb
operon that encodes a periplasmic membrane fusion protein
(PseE), and an ABC-type cytoplasmic membrane protein
(PseF). The PseEF efflux system exhibited amino acid homology
to a putative ABC efflux system (MacAB) of E. coli
W3104 with identities of 47.2% (i.e., PseE to MacA) and
57.6% (i.e., PseF to MacB). A nonpolar mutation within the
pseF gene was generated by nptII insertional mutagenesis.
The resultant mutant strain showed significant reduction in
secretion of syringomycin (74%) and syringopeptin (71%),
as compared to parental strain B301D. Quantitative real-time
RT-PCR was used to determine transcript levels of the syringomycin
(syrB1) and syringopeptin (sypA) synthetase
genes in strain B301D-HK7 (a pseF mutant). Expression of
the sypA gene by mutant strain B301D-HK7 was approximately
6.9% as compared to that of parental strain B301D,
while the syrB1 gene expression by mutant strain B301D-HK7
was nearly 14.6%. In addition, mutant strain B301D-HK7
was less virulent by approximately 67% than parental strain
B301D in immature cherry fruits. Mutant strain B301D-HK7
was not reduced in resistance to any antibiotics used in this
study as compared to parental strain B301D. Expression
(transcript levels) of the pseF gene was induced approximately
six times by strain B301D grown on syringomycin
minimum medium (SRM) supplemented with the plant signal
molecules arbutin and D-fructose (SRMAF), as compared to
that of strain B301D grown on SRM (in the absence of plant
signal molecules). In addition, during infection of bean
plants by P. syringae pv. syringae strain B728a, expression
of the pseF gene increased at 3 days after inoculation (dai).
More than 180-fold induction was observed in transcript
levels of the pseF gene by parental strain B728a as compared
to strain B728a-SL7 (a salA mutant). Thus, the PseEF
efflux system, an ABC-type efflux system, has an important
role in secretion of syringomycin and syringopeptin, and is
required for full virulence in P. syringae pv. syringae.
- Effects of a Dark-Septate Endophytic Isolate LBF-2 on the Medicinal Plant Lycium barbarum L.
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Hai-han Zhang , Ming Tang , Hui Chen , Ya-jun Wang
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J. Microbiol. 2012;50(1):91-96. Published online February 27, 2012
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DOI: https://doi.org/10.1007/s12275-012-1159-9
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Abstract
- Dark septate endophytes (DSE) are ubiquitous root associated
fungi; however, our understanding of their ecological
function remains unclear. Here, we investigated the positive
effect of a DSE fungus on its host plant Lycium barbarum
L. A DSE isolate, LBF-2, isolated from the roots of L. barbarum,
was inoculated onto the roots of plants, which were
grown under greenhouse conditions for five weeks. The result
of molecular analyses of internal transcribed spacer regions
indicated that LBF-2 was 96% similar to Paraphoma chrysanthemicola.
Melanized septate hyphae were observed in
the root cortical cells of L. barbarum using a light microscope.
Inoculation with LBF-2 increased the total biomass by 39.2%
and also enhanced chlorophyll fluorescence. Inoculation
increased the concentration of total chlorophyll by 22.8%
and of chlorophyll a by 21.3%, relative to uninoculated
controls. These data indicate that the LBF-2 isolate might
be used to facilitate the cultivation of L. barbarum, which
has medicinal applications.
- Heat- and Cold-Shock Responses in Fusarium graminearum 3 Acetyl- and 15 Acetyl-Deoxynivalenol Chemotypes
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Vladimir Vujanovic , Yit Kheng Goh , Prasad Daida
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J. Microbiol. 2012;50(1):97-102. Published online February 27, 2012
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DOI: https://doi.org/10.1007/s12275-012-1381-5
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Abstract
- Fusarium graminearum Schwabe is the primary cause of
Fusarium head blight (FHB) in North America. Chemically
distinct F. graminearum sub-populations can be identified
based on the type or composition of deoxynivalenol (DON)
mycotoxin derivatives, including 3-acetyl (3-ADON) and
15-acetyl (15-ADON). The evaluation of randomly selected
3-ADON and 15-ADON isolates, collected from spring
wheat throughout Canada, was performed using thin layer
chromatography (TLC), high-performance liquid chromatography
(HPLC), ice-nucleation activity (INA), and heat and
cold tolerance tests conducted within a temperature range
of -70°C to 65°C. The results indicated that the 3-ADON
sub-population, which is responsible for the highest disease
severity and has rapidly displaced the 15-ADON sub-population,
produces more DON and zearalenone (ZEA) than
the 15-ADON sub-population when exposed to heat and
cold. Following exposures (1 and 2 h) to extremely high or
low temperatures, 3-ADON isolates exhibited faster mycelial
growth than 15-ADON isolates. In addition, the warmest
temperature at which INA activity occurred was in 3-ADON
(-3.6°C) vs. 15-ADON (-5.1°C). Taken together, these features
suggest that the newly emerging 3-ADON sub-population
is more resilient than the resident 15-ADON sub-population.
Overall, the differences between the two sub-populations
could provide new insights into FHB epidemiology and if
validated under field conditions, may provide important
information for predicting future FHB epidemics.
Journal Article
- Chitinase Production by Bacillus thuringiensis and Bacillus licheniformis: Their Potential in Antifungal Biocontrol
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Eman Zakaria Gomaa
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J. Microbiol. 2012;50(1):103-111. Published online February 27, 2012
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DOI: https://doi.org/10.1007/s12275-012-1343-y
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Abstract
- Thirty bacterial strains were isolated from the rhizosphere
of plants collected from Egypt and screened for production
of chitinase enzymes. Bacillus thuringiensis NM101-19 and
Bacillus licheniformis NM120-17 had the highest chitinolytic
activities amongst those investigated. The production
of chitinase by B. thuringiensis and B. licheniformis was optimized
using colloidal chitin medium amended with 1.5%
colloidal chitin, with casein as a nitrogen source, at 30°C after
five days of incubation. An enhancement of chitinase production
by the two species was observed by addition of sugar
substances and dried fungal mats to the colloidal chitin
media. The optimal conditions for chitinase activity by B.
thuringiensis and B. licheniformis were at 40°C, pH 7.0 and
pH 8.0, respectively. Na+, Mg2+, Cu2+, and Ca2+ caused enhancement
of enzyme activities whereas they were markedly
inhibited by Zn2+, Hg2+, and Ag+. In vitro, B. thuringiensis
and B. licheniformis chitinases had potential for cell wall lysis
of many phytopathogenic fungi tested. The addition of B.
thuringiensis chitinase was more effective than that of B. licheniformis
in increasing the germination of soybean seeds
infected with various phytopathogenic fungi.
Research Support, Non-U.S. Gov't
- Saccharomyces cerevisiae Cmr1 Protein Preferentially Binds to UV-Damaged DNA In Vitro
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Do-Hee Choi , Sung-Hun Kwon , Joon-Ho Kim , Sung-Ho Bae
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J. Microbiol. 2012;50(1):112-118. Published online February 27, 2012
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DOI: https://doi.org/10.1007/s12275-012-1597-4
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Abstract
- DNA metabolic processes such as DNA replication, recombination,
and repair are fundamentally important for the
maintenance of genome integrity and cell viability. Although
a large number of proteins involved in these pathways have
been extensively studied, many proteins still remain to be
identified. In this study, we isolated DNA-binding proteins
from Saccharomyces cerevisiae using DNA-cellulose columns.
By analyzing the proteins using mass spectrometry, an uncharacterized
protein, Cmr1/YDL156W, was identified. Cmr1
showed sequence homology to human Damaged-DNA binding
protein 2 in its C-terminal WD40 repeats. Consistent
with this finding, the purified recombinant Cmr1 protein
was found to be intrinsically associated with DNA-binding
activity and exhibited higher affinity to UV-damaged DNA
substrates. Chromatin isolation experiments revealed that
Cmr1 localized in both the chromatin and supernatant
fractions, and the level of Cmr1 in the chromatin fraction
increased when yeast cells were irradiated with UV. These
results
suggest that Cmr1 may be involved in DNA-damage
responses in yeast.