scholarly journals The Endochitinase of Clonostachys Rosea Enhances the Biocontrol Efficiency of Bacillus Amyloliquefaciens by Increasing Its Activities of Defense Enzymes

2018 ◽  
Author(s):  
Yangyang Zheng ◽  
Xudong Wang ◽  
Siyuan Liu ◽  
Kewei Zhang ◽  
Zhibo Cai ◽  
...  
Keyword(s):  
Superoxide Dismutase ◽  
Bacillus Amyloliquefaciens ◽  
Chitinase Activity ◽  
Defense Enzymes ◽  
Wild Type ◽  
Clonostachys Rosea ◽  
Tomato Plants ◽  
Significant Difference ◽  
In The Wild ◽  
Related Enzyme

To investigate whether the ech42 gene in Clonostachys rosea can improve the biocontrol efficacy of Bacillus amyloliquefaciens and its molecular mechanism.Compared to the wild type, the B. amyloliquefaciens transformed with the ech42 gene exhibited a higher chitinase activity. The B. amyloliquefaciens-ech42 also showed a significantly higher biocontrol efficiency against B. cinerea when tomato plants were pre-treated with amyloliquefaciens-ech42. No significant difference of control efficiency was observed between the wild type and amyloliquefaciens-ech42 when tomato plants were first infected by B. cinerea. In addition, the activity of the defense-related enzyme polyphenol oxidase, but not superoxide dismutase was significantly higher in amyloliquefaciens-ech42 than in the wild type.The ech42 enhances the Bacillus amyloliquefaciens biocontrol efficiency by increasing the capacity of protection/prevention to plants, rather treating/killing the pathogens.

scholarly journals The Endochitinase of Clonostachysrosea Expression in Bacillus amyloliquefaciens Enhances the Botrytis cinerea Resistance of Tomato

2018 ◽  
Vol 19 (8) ◽  
pp. 2221 ◽  
Author(s):  
Yangyang Zheng ◽  
Xudong Wang ◽  
Siyuan Liu ◽  
Kewei Zhang ◽  
Zhibo Cai ◽  
...  
Keyword(s):  
Superoxide Dismutase ◽  
Botrytis Cinerea ◽  
Molecular Mechanism ◽  
Bacillus Amyloliquefaciens ◽  
Chitinase Activity ◽  
Wild Type ◽  
Tomato Plants ◽  
Significant Difference ◽  
In The Wild ◽  
Related Enzyme

To investigate whether the ech42 gene in Clonostachysrosea can improve the biocontrol efficacy of Bacillus amyloliquefaciens and its molecular mechanism. Compared to the wild type, the B. amyloliquefaciens transformed with the ech42 gene exhibited higher chitinase activity. The B. amyloliquefaciens-ech42 also showed significantly higher biocontrol efficiency compared to Botrytiscinerea when tomato plants were pre-treated with B. amyloliquefaciens-ech42. No significant difference in biocontrol efficiency was observed between the wild type and B.amyloliquefaciens-ech42 when tomato plants were first infected by Botrytiscinerea. In addition, the activity of the defense-related enzyme polyphenol oxidase, but not superoxide dismutase, was significantly higher in B. amyloliquefaciens-ech42 than in the wild type. The ech42 enhances the biocontrol efficiency of B.amyloliquefaciens by increasing the capacity of preventative/curative effects in plants, rather than by killing the pathogens.

scholarly journals Autoproteolysis of YscU of Yersinia pseudotuberculosis Is Important for Regulation of Expression and Secretion of Yop Proteins

2009 ◽  
Vol 191 (13) ◽  
pp. 4259-4267 ◽  
Author(s):  
Ann-Catrin Björnfot ◽  
Moa Lavander ◽  
Åke Forsberg ◽  
Hans Wolf-Watz
Keyword(s):  
Type Iii Secretion ◽  
Calcium Concentration ◽  
Wild Type Strain ◽  
Yersinia Pseudotuberculosis ◽  
Secretion System ◽  
Wild Type ◽  
Regulation Of Expression ◽  
Significant Difference ◽  
In The Wild ◽  
Needle Protein

ABSTRACT YscU of Yersinia can be autoproteolysed to generate a 10-kDa C-terminal polypeptide designated YscUCC. Autoproteolysis occurs at the conserved N↓PTH motif of YscU. The specific in-cis-generated point mutants N263A and P264A were found to be defective in proteolysis. Both mutants expressed and secreted Yop proteins (Yops) in calcium-containing medium (+Ca2+ conditions) and calcium-depleted medium (−Ca2+ conditions). The level of Yop and LcrV secretion by the N263A mutant was about 20% that of the wild-type strain, but there was no significant difference in the ratio of the different secreted Yops, including LcrV. The N263A mutant secreted LcrQ regardless of the calcium concentration in the medium, corroborating the observation that Yops were expressed and secreted in Ca2+-containing medium by the mutant. YscF, the type III secretion system (T3SS) needle protein, was secreted at elevated levels by the mutant compared to the wild type when bacteria were grown under +Ca2+ conditions. YscF secretion was induced in the mutant, as well as in the wild type, when the bacteria were incubated under −Ca2+ conditions, although the mutant secreted smaller amounts of YscF. The N263A mutant was cytotoxic for HeLa cells, demonstrating that the T3SS-mediated delivery of effectors was functional. We suggest that YscU blocks Yop release and that autoproteolysis is required to relieve this block.

The affinity of hemoglobin for oxygen affects ventilatory responses in mutant mice with Presbyterian hemoglobinopathy

2003 ◽  
Vol 285 (4) ◽  
pp. R747-R753 ◽  
Author(s):  
Masahiko Izumizaki ◽  
Masakatsu Tamaki ◽  
Yo-ichi Suzuki ◽  
Michiko Iwase ◽  
Takuji Shirasawa ◽  
...  
Keyword(s):  
Minute Ventilation ◽  
Globin Gene ◽  
Open Circuit ◽  
Mutant Mice ◽  
Whole Body ◽  
Wild Type ◽  
Peripheral Tissues ◽  
Ventilatory Responses ◽  
Significant Difference ◽  
In The Wild

The purpose of this study was to test whether chronically enhanced O2 delivery to tissues, without arterial hyperoxia, can change acute ventilatory responses to hypercapnia and hypoxia. The effects of decreased hemoglobin (Hb)-O2 affinity on ventilatory responses during hypercapnia (0, 5, 7, and 9% CO2 in O2) and hypoxia (10 and 15% O2 in N2) were assessed in mutant mice expressing Hb Presbyterian (mutation in the β-globin gene, β108 Asn → Lys). O2 consumption during normoxia, measured via open-circuit methods, was significantly higher in the mutant mice than in wild-type mice. Respiratory measurements were conducted with a whole body, unrestrained, single-chamber plethysmograph under conscious conditions. During hypercapnia, there was no difference between the slopes of the hypercapnic ventilatory responses, whereas minute ventilation at the same levels of arterial PCO2 was lower in the Presbyterian mice than in the wild-type mice. During both hypoxic exposures, ventilatory responses were blunted in the mutant mice compared with responses in the wild-type mice. The effects of brief hyperoxia exposure (100% O2) after 10% hypoxia on ventilation were examined in anesthetized, spontaneously breathing mice with a double-chamber plethysmograph. No significant difference was found in ventilatory responses to brief hypoxia between both groups of mice, indicating possible involvement of central mechanisms in blunted ventilatory responses to hypoxia in Presbyterian mice. We conclude that chronically enhanced O2 delivery to peripheral tissues can reduce ventilation during acute hypercapnic and hypoxic exposures.

scholarly journals Transcriptome Analysis of Aspergillus nidulans Exposed to Camptothecin-Induced DNA Damage

2006 ◽  
Vol 5 (10) ◽  
pp. 1688-1704 ◽  
Author(s):  
Iran Malavazi ◽  
Marcela Savoldi ◽  
Sônia Marli Zingaretti Di Mauro ◽  
Carlos Frederico Martins Menck ◽  
Steven D. Harris ◽  
...  
Keyword(s):  
Dna Damage ◽  
Aspergillus Nidulans ◽  
Mutant Strain ◽  
Deletion Mutant ◽  
Time Course ◽  
Excision Repair ◽  
Wild Type ◽  
Significant Difference ◽  
Mutant Strains ◽  
In The Wild

ABSTRACT We have used an Aspergillus nidulans macroarray carrying sequences of 2,787 genes from this fungus to monitor gene expression of both wild-type and uvsB ATR (the homologue of the ATR gene) deletion mutant strains in a time course exposure to camptothecin (CPT). The results revealed a total of 1,512 and 1,700 genes in the wild-type and uvsB ATR deletion mutant strains that displayed a statistically significant difference at at least one experimental time point. We characterized six genes that have increased mRNA expression in the presence of CPT in the wild-type strain relative to the uvsB ATR mutant strain: fhdA (encoding a forkhead-associated domain protein), tprA (encoding a hypothetical protein that contains a tetratrico peptide repeat), mshA (encoding a MutS homologue involved in mismatch repair), phbA (encoding a prohibitin homologue), uvsC RAD51 (the homologue of the RAD51 gene), and cshA (encoding a homologue of the excision repair protein ERCC-6 [Cockayne's syndrome protein]). The induced transcript levels of these genes in the presence of CPT require uvsB ATR. These genes were deleted, and surprisingly, only the ΔuvsC mutant strain was sensitive to CPT; however, the others displayed sensitivity to a range of DNA-damaging and oxidative stress agents. These results indicate that the selected genes when inactivated display very complex and heterogeneous sensitivity behavior during growth in the presence of agents that directly or indirectly cause DNA damage. Moreover, with the exception of UvsC, deletion of each of these genes partially suppressed the sensitivity of the ΔuvsB strain to menadione and paraquat. Our results provide the first insight into the overall complexity of the response to DNA damage in filamentous fungi and suggest that multiple pathways may act in parallel to mediate DNA repair.

Effects of FABP7 on functional recovery after spinal cord injury in adult mice

2019 ◽  
Vol 31 (2) ◽  
pp. 291-297 ◽  
Author(s):  
Nobuo Senbokuya ◽  
Hideyuki Yoshioka ◽  
Takashi Yagi ◽  
Yuji Owada ◽  
Hiroyuki Kinouchi
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Functional Recovery ◽  
Gene Knockout ◽  
Neuronal Injury ◽  
Wild Type ◽  
Fatty Acid Binding ◽  
Significant Difference ◽  
Cord Injury ◽  
In The Wild

OBJECTIVEElucidating the mechanisms of neuronal injury is crucial for the development of spinal cord injury (SCI) treatments. Brain-type fatty acid–binding protein 7 (FABP7) is expressed in the adult rodent brain, especially in astrocytes, and has been reported to play a role in astrocyte function in various types of brain damage; however, its role after SCI has not been well studied. In this study, the authors evaluated the expression change of FABP7 after SCI using a mouse spinal cord compression model and observed the effect of FABP7 gene knockout on neuronal damage and functional recovery after SCI.METHODSFemale FABP7 knockout (KO) mice with a C57BL/6 background and their respective wild-type littermates were subjected to SCI with a vascular clip. The expression of FABP7, neuronal injury, and functional recovery after SCI were analyzed in both groups of mice.RESULTSWestern blot analysis revealed upregulation of FABP7 in the wild-type mice, which reached its peak 14 days after SCI, with a significant difference in comparison to the control mice. Immunohistochemistry also showed upregulation of FABP7 at the same time points, mainly in proliferative astrocytes. The number of surviving ventral neurons in the FABP7-KO mice at 28 days after SCI was significantly lower than that observed in the wild-type mice. In addition, motor functional recovery in the FABP7-KO mice was significantly worse than that of the wild-type mice.CONCLUSIONSThe findings of this study indicate that FABP7 could have a neuroprotective role that might be associated with modulation of astrocytes after SCI. FABP7 could potentially be a therapeutic target in the treatment of SCI.

scholarly journals The Chitinolytic Activity of Listeria monocytogenes EGD Is Regulated by Carbohydrates but Also by the Virulence Regulator PrfA

2010 ◽  
Vol 76 (19) ◽  
pp. 6470-6476 ◽  
Author(s):  
M. H. Larsen ◽  
J. J. Leisner ◽  
H. Ingmer
Keyword(s):  
Listeria Monocytogenes ◽  
Virulence Gene ◽  
Chitinase Activity ◽  
Exponential Growth Phase ◽  
Wild Type ◽  
Chitinolytic Activity ◽  
Carbohydrate Polymers ◽  
Terrestrial Environments ◽  
In The Wild

ABSTRACT Chitin, an insoluble polymer of N-acetyl-d-glucosamine (GlcNAc), is one of the most abundant carbohydrate polymers in marine and terrestrial environments. Chitin hydrolysis by Listeria monocytogenes depends on two chitinase-encoding genes, chiA and chiB, and the aim of this study was to investigate their regulation. Chitin induces the expression of both chitinases in late exponential growth phase, and chiA but not chiB is furthermore induced by the monomer GlcNAc. Furthermore, their expression is subjected to catabolite control. Chitinases expressed by bacterial pathogens have proven to be important not only for nutrient acquisition and environmental survival but also for infecting animals and humans. Interestingly, the central L. monocytogenes virulence gene regulator, PrfA, is required for the chitinolytic phenotype, as chitinase activity was significantly reduced in prfA mutant cells compared to its level in wild-type cells. In agreement with this, Northern blot analysis showed that the amounts of chiA and chiB transcripts upon induction by chitin were significantly lower in the prfA mutant than in the wild type. The chitinolytic activity and chiA and chiB expression were reduced in the absence of the sigB gene, indicating that σB is also important for the production of chitinases. The chiA, chiB, and chiA chiB mutants were not impaired for in vitro adhesion and invasion in epithelial cell lines, but the chiA chiB double mutant showed less survival ability in a chitin-enriched medium. The regulation of chitinolytic activity in L. monocytogenes is complex, and taken together, the results indicate that the biological role of this activity may not be limited to the external environment.

scholarly journals DNA Fragmentation and Prolonged Expression of c-fos, c-jun, and hsp70 in Kainic Acid-Induced Neuronal Cell Death in Transgenic Mice Overexpressing Human CuZn-Superoxide Dismutase

1997 ◽  
Vol 17 (3) ◽  
pp. 241-256 ◽  
Author(s):  
Takeo Kondo ◽  
Frank R. Sharp ◽  
Jari Honkaniemi ◽  
Shigeki Mikawa ◽  
Charles J. Epstein ◽  
...  
Keyword(s):  
Cell Death ◽  
Superoxide Dismutase ◽  
Kainic Acid ◽  
Early Gene ◽  
Heat Shock Gene ◽  
Seizure Threshold ◽  
Wild Type ◽  
Significant Difference ◽  
Cuzn Superoxide Dismutase ◽  
The Brain

Kainic acid (KA) neurotoxicity was examined in transgenic (Tg) mice overexpressing human CuZn-superoxide dismutase (SOD-1). The doses of KA required to produce seizures, the severity of the seizures, and the regions damaged were similar in SOD-1 Tg and non-transgenic wild-type mice. Intraperitoneal KA injection induced seizure-related neuronal damage in the CA3 and CA1 regions of the hippocampus and in other regions of the brain in both SOD-1 Tg and wild-type mice. These damaged neurons were labeled with the terminal deoxynudeotidyl transferase-mediated uridine 5′—triphosphate-biotin nick end labeling (TUNEL) technique up to 72 h, although no significant difference in the number of TUNEL-positive neurons was observed between SOD-1 Tg and wild-type mice. In situ hybridization showed that c- fos, c- jun, and hsp70 genes were expressed in the hippocampus, cortex, and other regions of the brain after KA treatment. The expression of these genes was maximal 1 to 4 h following KA treatment but persisted longer in the hippocampus and other regions in SOD-1 Tg compared with wild-type mice; however, cell death in the hippocampus, assessed using cresyl violet staining, was similar in SOD-1 Tg and wild-type mice. The data show that superoxide radicals modulate both immediate early gene and heat shock gene expression after KA-induced seizures. The prolonged expression of c- fos, c- jun, and hsp70 in SOD-1 Tg compared with wild-type mice may indicate that hippocampal neurons survive longer in SOD-1 Tg than in wild-type animals; however, cell death as well as the seizure threshold, seizure severity and the pattern of regional vulnerability were not affected substantially by increased levels of SOD in the brain.

scholarly journals A change of the metal-specific activity of a cambialistic superoxide dismutase from Porphyromonas gingivalis by a double mutation of Gln-70 to Gly and Ala-142 to Gln

2000 ◽  
Vol 345 (2) ◽  
pp. 345-350 ◽  
Author(s):  
B. Yukihiro HIRAOKA ◽  
Fumiyuki YAMAKURA ◽  
Shigetoshi SUGIO ◽  
Koji NAKAYAMA
Keyword(s):  
Superoxide Dismutase ◽  
Porphyromonas Gingivalis ◽  
Active Site ◽  
Specific Activity ◽  
Amino Acid Sequences ◽  
Wild Type ◽  
Visible Absorption ◽  
Double Mutation ◽  
In The Wild ◽  
Specific Activities

Gln-70, which is located near the active-site metal, is conserved in aligned amino acid sequences of iron-containing superoxide dimutases (Fe-SODs) and cambialistic SOD from Porphyromonas gingivalis, but is complementarily substituted with Gln-142 in manganese-containing SODs (Mn-SODs). In order to clarify the contribution of this exchange of Gln to the metal-specific activity of P. gingivalis SOD, we have prepared a mutant of the enzyme with conversions of Gln-70 to Gly and Ala-142 to Gln. The ratio of the specific activities of Mn- to Fe-reconstituted P. gingivalis SOD increased from 1.4 in the wild-type to 3.5 in the mutant SODs. Furthermore, the visible absorption spectra of the Mn- and Fe-reconstituted mutant SODs more closely resembled that of Mn-specific SOD than that of the wild-type SOD. We conclude that a difference in configuration of the Gln residues of P. gingivalis SOD partially accounts for the metal-specific activity of the enzyme.

scholarly journals A yceI Gene Involves in the Adaptation of Ralstonia solanacearum to Methyl Gallate and Other Stresses

2021 ◽  
Vol 9 (9) ◽  
pp. 1982
Author(s):  
Kai-Hao Wang ◽  
De-Hong Zheng ◽  
Gao-Qing Yuan ◽  
Wei Lin ◽  
Qi-Qin Li
Keyword(s):  
Ralstonia Solanacearum ◽  
Wild Type Strain ◽  
Methyl Gallate ◽  
Wild Type ◽  
Lower Growth ◽  
Tomato Plants ◽  
Over Expression ◽  
Virulence Potential ◽  
Significant Difference ◽  
Expression Strain

Ralstonia solanacearum is a plant-pathogenic bacterium causing plant bacterial wilt, and can be strongly inhibited by methyl gallate (MG). Our previous transcriptome sequencing of MG-treated R. solanacearum showed that the yceI gene AVT05_RS03545 of Rs-T02 was up-regulated significantly under MG stress. In this study, a deletion mutant (named DM3545) and an over-expression strain (named OE3545) for yceI were constructed to confirm this hypothesis. No significant difference was observed among the growth of wild-type strain, DM3545, and OE3545 strains without MG treatment. Mutant DM3545 showed a lower growth ability than that of the wild type and OE3545 strains under MG treatment, non-optimal temperature, or 1% NaCl. The ability of DM3545 for rhizosphere colonization was lower than that of the wild-type and OE3545 strains. The DM3545 strain showed substantially reduced virulence toward tomato plants than its wild-type and OE3545 counterpart. Moreover, DM3545 was more sensitive to MG in plants than the wild-type and OE3545 strains. These results suggest that YceI is involved in the adaptability of R. solanacearum to the presence of MG and the effect of other tested abiotic stresses. This protein is also possibly engaged in the virulence potential of R. solanacearum.

scholarly journals Mua (HP0868) Is a Nickel-Binding Protein That Modulates Urease Activity in Helicobacter pylori

mBio ◽  
2011 ◽  
Vol 2 (2) ◽  
Author(s):  
Stéphane L. Benoit ◽  
Robert J. Maier
Keyword(s):  
Helicobacter Pylori ◽  
Urease Activity ◽  
Binding Protein ◽  
Total Protein Content ◽  
Nickel Concentration ◽  
Wild Type ◽  
Mobility Shift ◽  
Content Type ◽  
Significant Difference ◽  
In The Wild

ABSTRACTA novel mechanism aimed at controlling urease expression inHelicobacter pyloriin the presence of ample nickel is described. Higher urease activities were observed in anhp0868mutant (than in the wild type) in cells supplemented with nickel, suggesting that the HP0868 protein (herein named Mua formodulator ofureaseactivity) represses urease activity when nickel concentrations are ample. The increase in urease activity in the Δmuamutant was linked to an increase in urease transcription and synthesis, as shown by quantitative real-time PCR, SDS-PAGE, and immunoblotting against UreAB. Increased urease synthesis was also detected in a ΔmuaΔnikRdouble mutant strain. The Δmuamutant was more sensitive to nickel toxicity but more resistant to acid challenge than was the wild-type strain. Pure Mua protein binds 2 moles of Ni2+per mole of dimer. Electrophoretic mobility shift assays did not reveal any binding of Mua to theureApromoter or other selected promoters (nikR,arsRS,5′ ureB-sRNAp). Previous yeast two-hybrid studies indicated that Mua and RpoD may interact; however, only a weak interaction was detected via cross-linking with pure components and this could not be verified by another approach. There was no significant difference in the intracellular nickel level between wild-type andmuamutant cells. Taken together, our results suggest the HP0868 gene product represses urease transcription when nickel levels are high through an as-yet-uncharacterized mechanism, thus counterbalancing the well-described NikR-mediated activation.IMPORTANCEUrease is a nickel-containing enzyme that buffers both the cytoplasm and the periplasm ofHelicobacter pyloriby converting urea into ammonia and carbon dioxide. The enzyme is the most abundant protein inH. pylori, accounting for an estimated 10% of the total protein content of the cell, and it is essential for early colonization and virulence. Numerous studies have focused on the transcription of the structuralureABgenes and its control by the regulatory proteins NikR and ArsR. Here we propose that urease transcription is under the control of another Ni-binding protein besides NikR, the Mua (HP0868) protein. Our results suggest that the Mua protein represses urease transcription when nickel levels are high. This mechanism would counterbalance the NikR-mediated activation of urease and ensure that, in the presence of a high nickel concentration, urease activation is limited and does not lead to massive production of detrimental ammonia.

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