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- Delineating the Acquired Genetic Diversity and Multidrug Resistance in Alcaligenes from Poultry Farms and Nearby Soil.
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Abhilash Bhattacharjee, Anil Kumar Singh
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J. Microbiol. 2024;62(7):511-523. Published online June 21, 2024
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DOI: https://doi.org/10.1007/s12275-024-00129-w
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Abstract
- Alcaligenes faecalis is one of the most important and clinically significant environmental pathogens, increasing in importance due to its isolation from soil and nosocomial environments. The Gram-negative soil bacterium is associated with skin endocarditis, bacteremia, dysentery, meningitis, endophthalmitis, urinary tract infections, and pneumonia in patients. With emerging antibiotic resistance in A. faecalis, it has become crucial to understand the origin of such resistance genes within this clinically significant environmental and gut bacterium. In this research, we studied the impact of antibiotic overuse in poultry and its effect on developing resistance in A. faecalis. We sampled soil and faecal materials from five poultry farms, performed whole genome sequencing & analysis and identified four strains of A. faecalis. Furthermore, we characterized the genes in the genomic islands of A. faecalis isolates. We found four multidrug-resistant A. faecalis strains that showed resistance against vancomycin (MIC >1000 μg/ml), ceftazidime (50 μg/ml), colistin (50 μg/ml) and ciprofloxacin (50 μg/ml). From whole genome comparative analysis, we found more than 180 resistance genes compared to the reference sequence. Parts of our assembled contigs were found to be similar to different bacteria which included pbp1A and pbp2 imparting resistance to amoxicillin originally a part of Helicobacter and Bordetella pertussis. We also found the Mycobacterial insertion element IS6110 in the genomic islands of all four genomes. This prominent insertion element can be transferred and induce resistance to other bacterial genomes. The results thus are crucial in understanding the transfer of resistance genes in the environment and can help in developing regimes for antibiotic use in the food and poultry industry.
- Flavivirga spongiicola sp. nov. and Flavivirga abyssicola sp. nov., Isolated from Marine Environments
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Sung-Hyun Yang , Mi-Jeong Park , Hyun-Myung Oh , Yeong-Jun Park , Kae Kyoung Kwon
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J. Microbiol. 2024;62(1):11-19. Published online February 6, 2024
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DOI: https://doi.org/10.1007/s12275-023-00102-z
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Abstract
- Two novel Gram-stain-negative, strictly-aerobic, rod-shaped (1.2 ± 3.4 μm × 0.3 ± 0.7 μm), and non-motile marine bacterial
species, designated MEBiC05379T
and MEBiC07777T,
were isolated from a marine sponge Pseudaxinella sp. in Gangneung
City and deep-sea sediments of the Ulleung basin in the East Sea of Korea, respectively. The 16S rRNA gene sequence
analysis revealed high levels of similarities between these strains and members of the genus Flavivirga (97.0–98.4% sequence
identities). Both novel strains revealed as mesophilic, neutrophilic in pH and slightly halophilic. Similar to those of other Flavivirga
members, the primary cellular fatty acids of both strains were iso-C15:0, iso-C15:1 G, iso-C15:03-OH, and iso-C17:0 3-OH,
with MEBiC05379T
and MEBiC07777T
containing relatively higher proportions of C12:
0 and summed feature 3 (
C16:1ω7c
and/or C16:
1ω6c). In both taxa, the major isoprenoid quinone was MK-6. The DNA G + C contents of MEBiC05379T
and
MEBiC07777T
genomes were 32.62 and 32.46 mol%, respectively. Compared to other members of Flavivirga, both strains
exhibited similar DNA G + C ratio and fatty acids pattern, yet enzyme expression and carbon sources utilization pattern were
different. Genomes of the genus Flavivirga showed enzyme preferences to fucoidan and sulfated galactans. Considering the
monophyly rule, AAI values delineate the genus Flavivirga from adjacent genera calculated to be 76.0–78.7%. Based on
the phenotypic, genomic and biochemical data, strains for MEBiC05379T
and MEBiC07777T
thus represent two novel species
in the genus Flavivirga, for which the names Flavivirga spongiicola sp. nov. (
MEBiC05379T [= KCTC 92527
T = JCM
16662
T]), and Flavivirga abyssicola sp. nov. (
MEBiC07777T [= KCTC 92563
T = JCM 36477
T]) are proposed.
- Environmental Adaptation of Psychrophilic Bacteria Subtercola spp. Isolated from Various Cryospheric Habitats
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Hanbyul Lee , Yong-Joon Cho , Ahnna Cho , Ok-Sun Kim
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J. Microbiol. 2023;61(7):663-672. Published online August 24, 2023
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DOI: https://doi.org/10.1007/s12275-023-00068-y
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Abstract
- Subtercola boreus K300T
is a novel psychrophilic strain that was isolated from permanently cold groundwater in Finland
and has also been found in several places in Antarctica including lake, soil, and rocks. We performed genomic and transcriptomic
analyses of 5 strains from Antarctica and a type strain to understand their adaptation to different environments.
Interestingly, the isolates from rocks showed a low growth rate and smaller genome size than strains from the other isolation
sources (lake, soil, and groundwater). Based on these habitat-dependent characteristics, the strains could be classified
into two ecotypes, which showed differences in energy production, signal transduction, and transcription in the clusters of
orthologous groups of proteins (COGs) functional category. In addition, expression pattern changes revealed differences
in metabolic processes, including uric acid metabolism, DNA repair, major facilitator superfamily (MFS) transporters, and
xylose degradation, depending on the nutritional status of their habitats. These findings provide crucial insights into the
environmental adaptation of bacteria, highlighting genetic diversity and regulatory mechanisms that enable them to thrive
in the cryosphere.
- Chemokine CCL6 Plays Key Role in the Inhibitory Effect of Vitamin A on Norovirus Infection
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Heetae Lee , Giljae Lee , You-Hee Cho , Youngcheon Song , GwangPyo Ko
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J. Microbiol. 2023;61(5):579-587. Published online May 26, 2023
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DOI: https://doi.org/10.1007/s12275-023-00047-3
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Abstract
- Norovirus (NoV) is the most common viral cause of acute gastroenteritis worldwide. Vitamin A has demonstrated the
potential to protect against gastrointestinal infections. However, the effects of vitamin A on human norovirus (HuNoV)
infections remain poorly understood. This study aimed to investigate how vitamin A administration affects NoV replication.
We demonstrated that treatment with retinol or retinoic acid (RA) inhibited NoV replication in vitro based on their effects
on HuNoV replicon-bearing cells and murine norovirus-1 (MNV-1) replication in murine cells. MNV replication in vitro
showed significant transcriptomic changes, which were partially reversed by retinol treatment. RNAi knockdown of CCL6,
a chemokine gene that was downregulated by MNV infection but upregulated by retinol administration, resulted in increased
MNV replication in vitro. This suggested a role of CCL6 in the host response to MNV infections. Similar gene expression
patterns were observed in the murine intestine after oral administration of RA and/or MNV-1.CW1. CCL6 directly decreased
HuNoV replication in HG23 cells, and might indirectly regulate the immune response against NoV infection. Finally, relative
replication levels of MNV-1.CW1 and MNV-1.CR6 were significantly increased in CCL6 knockout RAW 264.7 cells. This
study is the first to comprehensively profile transcriptomes in response to NoV infection and vitamin A treatment in vitro,
and thus may provide new insights into dietary prophylaxis and NoV infections.
- Coumarin-based combined computational study to design novel drugs against Candida albicans
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Akhilesh Kumar Maurya , Nidhi Mishra
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J. Microbiol. 2022;60(12):1201-1207. Published online November 10, 2022
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DOI: https://doi.org/10.1007/s12275-022-2279-5
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Abstract
- Candida species cause the most prevalent fungal illness, candidiasis.
Candida albicans is known to cause bloodstream infections.
This species is a commensal bacterium, but it can
cause hospital–acquired diseases, particularly in COVID-19
patients with impaired immune systems. Candida infections
have increased in patients with acute respiratory distress syndrome.
Coumarins are both naturally occurring and synthetically
produced. In this study, the biological activity of 40 coumarin
derivatives was used to create a three-dimensional quantitative
structure activity relationship (3D-QSAR) model. The
training and test minimum inhibitory concentration values
of C. albicans active compounds were split, and a regression
model based on statistical data was established. This model
served as a foundation for the creation of coumarin derivative
QSARs. This is a unique way to create new therapeutic compounds
for various ailments. We constructed novel structural
coumarin derivatives using the derived QSAR model, and the
models were confirmed using molecular docking and molecular
dynamics simulation.
- Eradication of drug-resistant Acinetobacter baumannii by cell-penetrating peptide fused endolysin
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Jeonghyun Lim , Jaeyeon Jang , Heejoon Myung , Miryoung Song
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J. Microbiol. 2022;60(8):859-866. Published online May 25, 2022
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DOI: https://doi.org/10.1007/s12275-022-2107-y
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Abstract
- Antimicrobial agents targeting peptidoglycan have shown
successful results in eliminating bacteria with high selective
toxicity. Bacteriophage encoded endolysin as an alternative
antibiotics is a peptidoglycan degrading enzyme with a low
rate of resistance. Here, the engineered endolysin was developed
to defeat multiple drug-resistant (MDR) Acinetobacter
baumannii. First, putative endolysin PA90 was predicted by
genome analysis of isolated Pseudomonas phage PBPA. The
His-tagged PA90 was purified from BL21(DE3) pLysS and
tested for the enzymatic activity using Gram-negative pathogens
known for having a high antibiotic resistance rate including
A. baumannii. Since the measured activity of PA90
was low, probably due to the outer membrane, cell-penetrating
peptide (CPP) DS4.3 was introduced at the N-terminus
of PA90 to aid access to its substrate. This engineered endolysin,
DS-PA90, completely killed A. baumannii at 0.25 μM,
at which concentration PA90 could only eliminate less than
one log in CFU/ml. Additionally, DS-PA90 has tolerance to
NaCl, where the ~50% of activity could be maintained in the
presence of 150 mM NaCl, and stable activity was also observed
with changes in pH or temperature. Even MDR A. baumannii
strains were highly susceptible to DS-PA90 treatment:
five out of nine strains were entirely killed and four strains
were reduced by 3–4 log in CFU/ml. Consequently, DS-PA90
could protect waxworm from A. baumannii-induced death
by ~70% for ATCC 17978 or ~44% for MDR strain 1656-2
infection. Collectively, our data suggest that CPP-fused endolysin
can be an effective antibacterial agent against Gramnegative
pathogens regardless of antibiotics resistance mechanisms.
- Lactobacillus plantarum-derived metabolites sensitize the tumorsuppressive effects of butyrate by regulating the functional expression of SMCT1 in 5-FU-resistant colorectal cancer cells
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Hye-Ju Kim , JaeJin An , Eun-Mi Ha
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J. Microbiol. 2022;60(1):100-117. Published online December 29, 2021
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DOI: https://doi.org/10.1007/s12275-022-1533-1
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Abstract
- A critical obstacle to the successful treatment of colorectal
cancer (CRC) is chemoresistance. Chemoresistant CRC cells
contribute to treatment failure by providing a mechanism
of drug lethargy and modifying chemoresistance-associated
molecules. The gut microbiota provide prophylactic and therapeutic
effects by targeting CRC through anticancer mechanisms.
Among them, Lactobacillus plantarum contributes
to the health of the host and is clinically effective in treating
CRC. This study confirmed that 5-fluorouracil (5-FU)-resistant
CRC HCT116 (HCT116/5FUR) cells acquired butyrateinsensitive
properties. To date, the relationship between 5-
FU-resistant CRC and butyrate resistance has not been elucidated.
Here, we demonstrated that the acquisition of butyrate
resistance in HCT116/5FUR cells was strongly correlated
with the inhibition of the expression and function of
SMCT1, a major transporter of butyrate in colonocytes. L.
plantarum-cultured cell-free supernatant (LP) restored the
functional expression of SMCT1 in HCT116/5FUR cells, leading
to butyrate-induced antiproliferative effect and apoptosis.
These results suggest that LP has a synergistic effect on the
SMCT1/butyrate-mediated tumor suppressor function and
is a potential chemosensitizer to overcome dual 5-FU and butyrate
resistance in HCT116 cells.
- The role of Jacalin-related lectin gene AOL_s00083g511 in the development and pathogenicity of the nematophagous fungus Arthrobotrys oligospora
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Xinyuan Dong , Jiali Si , Guanghui Zhang , Zhen Shen , Li Zhang , Kangliang Sheng , Jingmin Wang , Xiaowei Kong , Xiangdong Zha , Yongzhong Wang
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J. Microbiol. 2021;59(8):736-745. Published online July 5, 2021
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DOI: https://doi.org/10.1007/s12275-021-1029-4
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Abstract
- Arthrobotrys oligospora is a model species of nematophagous
fungi and has great potential for the biological control of nematode
diseases. Lectin is a protein that binds to carbohydrates
and their complexes with high specificity, which mediates recognition
events in various physiological and pathological
processes. This study aimed to investigate the role of the
Jacalin-related lectin (JRL) gene, AOL_s00083g511, in A. oligospora
development. Through a homology recombination
approach, we obtained the AOL_s00083g511 knockout mutant
strain (Δg511). Next, the biological characteristics of the
Δg511 mutant strain, including growth rate, conidia germination
rate, adaptation to environmental stresses, and nematocidal
activity, were compared with those of the wild-type
(WT) strain. The results showed that the JRL gene AOL_
s00083g511 did not affect fungal growth, conidia germination,
3D-trap formation, and the ability of A. oligospora to
prey on nematodes significantly. We speculate that this phenomenon
may be caused by a loss of the key β1–β2 loops in
the AOL_ s00083g511-encoded JRL domain and an intrinsic
genetic compensation of AOL_s00083g511 in this fungus.
The growth rates of both strains on high salt or surfactant media
were similar; however, in the strong oxidation medium,
the growth rate of the Δg511 mutant was significantly lower
than that of the WT strain, indicating that AOL_s00083g511
might play a role in oxidative stress resistance. These findings
provide a basis for further analysis of the related functions
of the JRL gene in A. oligospora and their potential roles
in the biological control of nematodes in the future.
Review
- [MINIREVIEW]Gain and loss of antibiotic resistant genes in multidrug resistant bacteria: One Health perspective
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Misung Kim , Jaeeun Park , Mingyeong Kang , Jihye Yang , Woojun Park
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J. Microbiol. 2021;59(6):535-545. Published online April 20, 2021
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DOI: https://doi.org/10.1007/s12275-021-1085-9
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Abstract
- The emergence of multidrug resistance (MDR) has become
a global health threat due to the increasing unnecessary use
of antibiotics. Multidrug resistant bacteria occur mainly by
accumulating resistance genes on mobile genetic elements
(MGEs), made possible by horizontal gene transfer (HGT).
Humans and animal guts along with natural and engineered
environments such as wastewater treatment plants and manured
soils have proven to be the major reservoirs and hotspots
of spreading antibiotic resistance genes (ARGs). As those
environments support the dissemination of MGEs through
the complex interactions that take place at the human-animalenvironment
interfaces, a growing One Health challenge is
for multiple sectors to communicate and work together to
prevent the emergence and spread of MDR bacteria. However,
maintenance of ARGs in a bacterial chromosome and/or
plasmids in the environments might place energy burdens
on bacterial fitness in the absence of antibiotics, and those
unnecessary ARGs could eventually be lost. This review highlights
and summarizes the current investigations into the gain
and loss of ARG genes in MDR bacteria among human-animal-
environment interfaces. We also suggest alternative treatments
such as combinatory therapies or sequential use of different
classes of antibiotics/adjuvants, treatment with enzymeinhibitors,
and phage therapy with antibiotics to solve the
MDR problem from the perspective of One Health issues.
Journal Articles
- Molecular characterization of Hsf1 as a master regulator of heat shock response in the thermotolerant methylotrophic yeast Ogataea parapolymorpha
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Jin Ho Choo , Su-Bin Lee , Hye Yun Moon , Kun Hwa Lee , Su Jin Yoo , Keun Pil Kim , Hyun Ah Kang
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J. Microbiol. 2021;59(2):151-163. Published online February 1, 2021
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DOI: https://doi.org/10.1007/s12275-021-0646-2
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Abstract
- Ogataea parapolymorpha (Hansenula polymorpha DL-1) is
a thermotolerant methylotrophic yeast with biotechnological
applications. Here, O. parapolymorpha genes whose expression
is induced in response to heat shock were identified by
transcriptome analysis and shown to possess heat shock elements
(HSEs) in their promoters. The function of O. parapolymorpha
HSF1 encoding a putative heat shock transcription
factor 1 (OpHsf1) was characterized in the context of heat
stress response. Despite exhibiting low sequence identity
(26%) to its Saccharomyces cerevisiae homolog, OpHsf1 harbors
conserved domains including a DNA binding domain
(DBD), domains involved in trimerization (TRI), transcriptional
activation (AR1, AR2), transcriptional repression (CE2),
and a C-terminal modulator (CTM) domain. OpHSF1 could
complement the temperature sensitive (Ts) phenotype of a
S. cerevisiae hsf1 mutant. An O. parapolymorpha strain with
an H221R mutation in the DBD domain of OpHsf1 exhibited
significantly retarded growth and a Ts phenotype. Intriguingly,
the expression of heat-shock-protein‒coding genes harboring
HSEs was significantly decreased in the H221R mutant
strain, even under non-stress conditions, indicating the importance
of the DBD for the basal growth of O. parapolymorpha.
Notably, even though the deletion of C-terminal domains
(ΔCE2, ΔAR2, ΔCTM) of OpHsf1 destroyed complementation
of the growth defect of the S. cerevisiae hsf1 strain,
the C-terminal domains were shown to be dispensable in O.
parapolymorpha. Overexpression of OpHsf1 in S. cerevisiae
increased resistance to transient heat shock, supporting the
idea that OpHsf1 could be useful in the development of heatshock‒
resistant yeast host strains.
- [PROTOCOL] High-throughput cultivation based on dilution-to-extinction with catalase supplementation and a case study of cultivating acI bacteria from Lake Soyang
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Suhyun Kim , Miri S. Park , Jaeho Song , Ilnam Kang , Jang-Cheon Cho
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J. Microbiol. 2020;58(11):893-905. Published online October 30, 2020
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DOI: https://doi.org/10.1007/s12275-020-0452-2
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Abstract
- Multi-omics approaches, including metagenomics and single-
cell amplified genomics, have revolutionized our understanding
of the hidden diversity and function of microbes
in nature. Even in the omics age, cultivation is an essential
discipline in microbial ecology since microbial cultures are
necessary to assess the validity of an in silico prediction about
the microbial metabolism and to isolate viruses infecting bacteria
and archaea. However, the ecophysiological characteristics
of predominant freshwater bacterial lineages remain
largely unknown due to the scarcity of cultured representatives.
In an ongoing effort to cultivate the uncultured majority
of freshwater bacteria, the most abundant freshwater
Actinobacteria acI clade has recently been cultivated from
Lake Soyang through catalase-supplemented high-throughput
cultivation based on dilution-to-extinction. This method
involves physical isolation of target microbes from mixed populations,
culture media simulating natural habitats, and removal
of toxic compounds. In this protocol, we describe detailed
procedures for isolating freshwater oligotrophic microbes,
as well as the essence of the dilution-to-extinction culturing.
As a case study employing the catalase-supplemented
dilution-to-extinction protocol, we also report a cultivation
trial using a water sample collected from Lake Soyang. Of the
480 cultivation wells inoculated with a single lake-water sample,
75 new acI strains belonging to 8 acI tribes (acI-A1, A2,
A4, A5, A6, A7, B1, B4, C1, and C2) were cultivated, and each
representative strain per subclade could be revived from glycerol
stocks. These cultivation results demonstrate that the
protocol described in this study is efficient in isolating freshwater
bacterioplankton harboring streamlined genomes.
- Anti-inflammatory and anti-oxidative effect of Korean propolis on Helicobacter pylori-induced gastric damage in vitro
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Moon-Young Song , Da-Young Lee , Eun-Hee Kim
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J. Microbiol. 2020;58(10):878-885. Published online September 2, 2020
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DOI: https://doi.org/10.1007/s12275-020-0277-z
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Abstract
- Helicobacter pylori, present in the stomach lining, is a Gramnegative
bacterium that causes various gastrointestinal diseases,
including gastritis and peptic ulcers. Propolis is a natural
resinous substance collected from a variety of plants,
and contains several natural bioactive substances. The aim of
this study was to investigate the anti-inflammatory and antioxidative
effects of Korean propolis on H. pylori-induced damage
in the human adenocarcinoma gastric cell line. The propolis
used in this study was obtained from the Korea Beekeeping
Association in South Korea. The expression of pro-inflammatory
interleukins (ILs), such as IL-8, IL-12, IL-1β, tumor
necrosis factor alpha, cyclooxygenase-2, and inducible
nitric oxide synthase, which was increased after H. pylori infection,
significantly decreased in a dose-dependent manner
upon pretreatment with Korean propolis, because of the suppression
of mitogen-activated protein kinases and nuclear
factor κB pathway. The anti-oxidative activity of propolis was
assessed using the 2,2-diphenyl-1-picrylhydrazyl hydrate free
radical assay. Korean propolis showed significant anti-oxidative
effects via reactive oxygen species scavenging. In addition,
pretreatment with Korean propolis upregulated the
expression of anti-oxidant enzymes through Nrf2 signaling
activation. These findings indicate that the use of Korean propolis,
which has anti-inflammatory and anti-oxidative effects,
can be promising for the prevention of H. pylori-induced gastric
damage.
- The effects of deletion of cellobiohydrolase genes on carbon source-dependent growth and enzymatic lignocellulose hydrolysis in Trichoderma reesei
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Meibin Ren , Yifan Wang , Guoxin Liu , Bin Zuo , Yuancheng Zhang , Yunhe Wang , Weifeng Liu , Xiangmei Liu , Yaohua Zhong
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J. Microbiol. 2020;58(8):687-695. Published online June 10, 2020
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DOI: https://doi.org/10.1007/s12275-020-9630-5
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Abstract
- The saprophytic fungus Trichoderma reesei has long been used
as a model to study microbial degradation of lignocellulosic
biomass. The major cellulolytic enzymes of T. reesei are the
cellobiohydrolases CBH1 and CBH2, which constitute more
than 70% of total proteins secreted by the fungus. However,
their physiological functions and effects on enzymatic hydrolysis
of cellulose substrates are not sufficiently elucidated.
Here, the cellobiohydrolase-encoding genes cbh1 and cbh2
were deleted, individually or combinatively, by using an auxotrophic
marker-recycling technique in T. reesei. When cultured
on media with different soluble carbon sources, all three
deletion strains (Δcbh1, Δcbh2, and Δcbh1Δcbh2) exhibited
no dramatic variation in morphological phenotypes, but their
growth rates increased apparently when cultured on soluble
cellulase-inducing carbon sources. In addition, Δcbh1 showed
dramatically reduced growth and Δcbh1Δcbh2 could hardly
grew on microcrystalline cellulose (MCC), whereas all strains
grew equally on sodium carboxymethyl cellulose (CMC-Na),
suggesting that the influence of the CBHs on growth was carbon
source-dependent. Moreover, five representative cellulose
substrates were used to analyse the influence of the absence
of CBHs on saccharification efficiency. CBH1 deficiency
significantly affected the enzymatic hydrolysis rates of various
cellulose substrates, where acid pre-treated corn stover
(PCS) was influenced the least. CBH2 deficiency reduced the
hydrolysis of MCC, PCS, and acid pre-treated and delignified
corncob but improved the hydrolysis ability of filter paper.
These results demonstrate the specific contributions of
CBHs to the hydrolysis of different types of biomass, which
could facilitate the development of tailor-made strains with
highly efficient hydrolysis enzymes for certain biomass types
in the biofuel industry.
Retracted Publication
- Cryptic prophages in a blaNDM-1-bearing plasmid increase bacterial survival against high NaCl concentration, high and low temperatures, and oxidative and immunological stressors
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So Yeon Kim , Kwan Soo Ko
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J. Microbiol. 2020;58(6):483-488. Published online March 28, 2020
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DOI: https://doi.org/10.1007/s12275-020-9605-6
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Abstract
- In this study, we investigated the effect of cryptic prophage
regions in a blaNDM-1-bearing plasmid, which was identified in
a patient from South Korea, on the survival of bacteria against
adverse environmental conditions. First, we conjugated the
intact plasmid and plasmids with deleted cryptic prophages
into Escherichia coli DH5α. The E. coli transconjugants carrying
the plasmid with intact cryptic prophages showed increased
survival during treatment with a high concentration
of NaCl, high and low temperatures, an oxidative stressor
(H2O2), and an immunological stressor (human serum). By
contrast, the transconjugants carrying the plasmid with a
single-cryptic prophage knockout did not show any change
in survival rates. mRNA expression analyses revealed that the
genes encoding sigma factor proteins were highly upregulated
by the tested stressors and affected the expression of
various proteins (antioxidant, cell osmosis-related, heat shock,
cold shock, and universal stress proteins) associated with the
specific defense against each stress. These findings indicate
that a bacterial strain carrying a plasmid with intact carbapenemase
gene and cryptic prophage regions exhibited an increased
resistance against simulated environmental stresses,
and cryptic prophages in the plasmid might contribute to this
enhanced stress resistance. Our study indicated that the coselection
of antibiotic resistance and resistance to other stresses
may help bacteria to increase survival rates against adverse
environments and disseminate.
Published Erratum
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