• Korean Journal of Pharmacognosy
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• v.44 no.3
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• pp.209-219
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• 2013

Heat shock protein 90 (Hsp90) is a molecular chaperone that assists protein folding and contributes to the stability of various proteins. It also stabilizes a number of proteins involved in tumor growth to consider it as a promising target for the treatment of cancer. Natural products have been a rich source of agents of value in medicine, therefore discovering lead compounds from them is one of important strategy in the drug development. In this regard, geldanamycin, radicicol, novobiocin and celastrol have been utilized as leads for the development of Hsp90 inhibitory anticancer agents. This review summerizes recent findings of natural products as Hsp90 inhibitiors. The Hsp90 inhibitory activities, mode of actions on Hsp90 and cytotoxicities on human cancer cell lines of natural products including bulgarialactone B, curcumin, (-)-gambogic acid, quercetin, sansalvamide A, silybin, and withaferin A were discussed.

• Microbiology and Biotechnology Letters
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• v.47 no.3
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• pp.337-342
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• 2019

We published that bacterial heme was over-produced in a recombinant Corynebacterium glutamicum expressing 5-aminolevulinic acid synthase ($hemA^+$) under control of a constitutive promoter ($P_{180}$) and the heme-producing C. glutamicum had commercial potentials; as an iron feed additive for swine and as a preservative for lactic acid bacteria. To enhance the heme production, the $hemA^+$ gene was expressed under controls of various promoters in the recombinant C. glutamicum. The $hemA^+$ expression by $P_{gapA}$ (a constitutive glycolytic promoter of glyceraldehyde-3-phosphate dehydrogenase) led 75% increase of heme production while the expression by $P_{H36}$ (a constitutive, very strong synthetic promoter) resulted in 50% decrease compared with the control ($hemA^+$ expression by $P_{180}$ constitutive promoter). The $hemA^+$ expression by a late log-phase activating $P_{sod}$ (an oxidative-stress responding promoter of superoxide dismutase) led 50% greater heme production than the control. The $hemA^+$ expression led by a heat-shock responding chaperone promoter ($P_{dnaK}$) resulted in 121% increase of heme production at the optimized heat-shock conditions. The promoter strength and induction phase are discussed based on the results for the heme production at an industrial scale.

• Biomolecules & Therapeutics
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• v.32 no.1
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• pp.115-122
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• 2024

Heat shock protein (HSP) 90 is expressed in most living organisms, and several client proteins of HSP90 are necessary for cancer cell survival and growth. Previously, we found that HSP90 was cleaved by histone deacetylase (HDAC) inhibitors and proteasome inhibitors, and the cleavage of HSP90 contributes to their cytotoxicity in K562 leukemia cells. In this study, we first established mouse xenograft models with K562 cells expressing the wild-type or cleavage-resistant mutant HSP90β and found that the suppression of tumor growth by the HDAC inhibitor suberoylanilide hydroxamic acid (SAHA) was interrupted by the mutation inhibiting the HSP90 cleavage in vivo. Next, we investigated the possible function of thioredoxin interacting protein (TXNIP) in the HSP90 cleavage induced by SAHA. TXNIP is a negative regulator for thioredoxin, an antioxidant protein. SAHA transcriptionally induced the expression of TXNIP in K562 cells. HSP90 cleavage was induced by SAHA also in the thymocytes of normal mice and suppressed by an anti-oxidant and pan-caspase inhibitor. When the thymocytes from the TXNIP knockout mice and their wild-type littermate control mice were treated with SAHA, the HSP90 cleavage was detected in the thymocytes of the littermate controls but suppressed in those of the TXNIP knockout mice suggesting the requirement of TXNIP for HSP90 cleavage. We additionally found that HSP90 cleavage was induced by actinomycin D, β-mercaptoethanol, and p38 MAPK inhibitor PD169316 suggesting its prevalence. Taken together, we suggest that HSP90 cleavage occurs also in vivo and contributes to the anti-cancer activity of various drugs in a TXNIP-dependent manner.

• Korean Journal of Microbiology
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• v.38 no.2
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• pp.67-73
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• 2002

The cellular responses of soil-borne bacterium, Pseudomonas sp. HK-6 to explosive 2,4,6-trinitrotoluene (TNT) were examined. Two stress shock proteins (SSPs), approximately 70-kDa DnaK and a 60-kDa GroEL were found in HK-6 cells in response to TNT. Analyses of SDS-PAGE and Western blot using anti-DnaK and GroEL revealed that SSPs were induced in HK-6 cells exposed to 0.5 M of TNT far 6-12 hrs. The maximum induction of proteins was achieved at 8-hr incubation point after HK-6 cells'exposure to TNT. Similar SSPs were found to be induced in HK-6 cells by heat shock (shift of temperature, from $30^{\circ}C$ to $42^{\circ}C$) or cold shock (shift of temperature,$30^{\circ}C$ to $4^{\circ}C$).2D-PAGE of soluble protein tractions from the culture of Pseudomonas sp. HX-6 exposed to TNT demonstrated that approximately 450 spots were observed on the silver stained gels ranging from pH 3 to pH 10. Among them, 12 spots significantly induced and expressed in response to TNT were selected and analyzed. Approximately 60-kDa protein, which was assumed highly expressed on the gel, was used for amino acid sequencing. N-terminal microsequencing with in-gel digestion showed that N-terminal sequence of the TNT-induced protein, <$^1XXAKDVKFGDSARKKML^17$, shared extensive similarity with $^1XXAKDVKFGDSARKKML^17$, N-terminal sequence of (P48216) GroEL of Pseudomonas putida.

• Journal of The Korean Society of Clinical Toxicology
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• v.16 no.2
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• pp.86-92
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• 2018

Purpose: Cardiovascular or respiratory complications of acute intoxication are the most common causes of mortality. Advanced cardiac life support (ACLS) or specific antidotes help manage these cardiac or respiratory complications in acute intoxication. On the other hand, some cases do not respond to ACLS or antidotes and they require some special treatment, such as extracorporeal life support (ECLS). ECLS will provide the chance of recovery from acute intoxication. This study examined the optimal timing of ECLS in acute intoxication cases. Methods: This paper is a brief report of a case series about ECLS in acute poisoning. The cases of ECLS were reviewed and the effects of ECLS on the blood pressure and serum lactate level of the patients were analyzed. Results: A total of four cases were reviewed; three of them were antihypertensive agent-induced shock, and one was respiratory failure after the inhalation of acid. The time range of ECLS application was 4.8-23.5 hours after toxic exposure. The causes of ECLS implementation were one for recurrent cardiac arrest, two for shock that did not respond to ACLS, and one for respiratory failure that did not respond to mechanical ventilator support. Three patients showed an improvement in blood pressure and serum lactate level and were discharged alive. In case 1, ECLS was stared at 23.5 hours post toxic exposure; the patient died due to refractory shock and multiple organ failure. Conclusion: The specific management of ECLS should be considered when a patient with acute intoxication does not recovery from shock or respiratory failure despite ACLS, antidote therapies, or mechanical ventilator support. ECLS improved the hemodynamic and ventilator condition in complicated poisoned patients. The early application of ECLS may improve the tissue perfusion state and outcomes of these patients before the toxic damage becomes irreversible.

• Journal of Microbiology and Biotechnology
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• v.17 no.8
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• pp.1353-1360
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• 2007

Three csp-like genes were identified in the Corynebacterium glutamicum genome and designated cspA, cspB, and cspA2. The genes cspA and cspA2 encode proteins, comprising of 67 amino acid residues, respectively. They share 83% identity with each other. Identity of those proteins with Escherichia coli Csp proteins was near 50%. The cspB gene encodes a protein composed of 127 amino acids, which has 40% and 35% sequence identity with CspA and CspA2, respectively, especially at its N-terminal region. Analysis of the gene expression profiles was done using transcriptional cat fusion, which identified not only active expression of the three genes at the physiological growth temperature of $30^{\circ}C$ but also growth phase-dependent expression with the highest activity at late log phase. The promoters of cspA and cspA2 were more active than that of cspB. The expression of the two genes increased by 30% after a temperature downshift to $15^{\circ}C$, and such stimulation was more evident in the late growth phase. In addition, the cspA gene appeared to show DNA-binding activity in vivo, and the activity increased at lower temperatures. Interestingly, the presence of cspA in multicopy hindered the growth of the host C. glutamicum cells at $20^{\circ}C$, but not at $30^{\circ}C$. Altogether, these data suggest that cspA, cspB, and cspA2 perform functions related to cold shock as well as normal cellular physiology. Moreover, CspA and its ortholog CspA2 may perform additional functions as a transcriptional regulator.

• Journal of Periodontal and Implant Science
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• v.38 no.4
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• pp.565-578
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• 2008

Purpose: Porphyromonas gingivalis(P. gingivalis) heat shock protein (HSP)60 may play a role in the immunopathogenesis of periodontitis as well as atherosclerosis by modulating autoimmune reaction due to its high level of sequence homology between bacteria and human counterpart. The purpose of this study was to identify immunodomiant epitope of P. gingivalis HSP60 that is reactive exclusively to the homologous bacteria without reacting with human HSP. Materials and methods: The present study was performed to identify the peptide specifically recognized by anti-P. gingivalis HSP60 monoclonal antibodies mono-reactive to P. gingivalis HSP60. Results: Four different hybridomas were cloned producing monoclonal IgG antibodies exclusively to P. gingivalis HSP60. Thirty seven synthetic peptides (20-mer with 5-amino acid overlapping) were synthesized. All of these peptide were subject to SDS-PAGE for immunblot analysis. One peptide (TVPGGGTTYIRAIAALEGLK) and the other peptide (TLVVNRLRGSLKICAVKAPG) were recognized by all and one of the four monoclonal antibodies, respectively, that reacted solely with P. gingivalis HSP60. Immunohistochemistry to identify the localization of the HSP60 in the diseased gingival tissues revealed that all of the four monoclonal antibodies were highly reacted with the diseased gingival tissue than normal gingival tissue. Conclusion: The P. gingivalis HSP60 peptides (TVPGGGTTYIRAIAALEGLK and TLVVNRLRGSLKICAVKAPG, respectively) are positively involved in the immunopathologic process of periodontal disease. The peptide may potentially be developed as vaccine candidates. Further investigations are under way to identify more clones producing monoclonal antibodies reactive to P. gingivalis HSP and to other periodontopathogenic bacteria as well, while maintaining specificities to human counterpart.

• Environmental Analysis Health and Toxicology
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• v.29
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• pp.2.1-2.7
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• 2014

Objectives Heat shock protein 90 (HSP90) is a highly conserved molecular chaperone important in the maturation of a broad spectrum of protein. In this study, an HSP90 gene was isolated from Asian paddle crab, Charybdis japonica, as a bio-indicator to monitor the marine ecosystem. Methods This work reports the responses of C. japonica HSP90 mRNA expression to cellular stress by endocrine disrupting chemicals (EDCs), such as bisphenol A (BPA) and 4-nonylphenol (NP) using real-time. reverse transcription polymerase chain reaction. Results The deduced amino acid sequence of HSP90 from C. japonica shared a high degree of homology with their homologues in other species. In a phylogenetic analysis, C. japonica HSP90 is evolutionally related with an ortholog of the other crustacean species. The expression of HSP90 gene was almost distributed in all the examined tissues of the C. japonica crab but expression levels varied among the different body parts of the crabs. We examined HSP90 mRNA expression pattern in C. japonica crabs exposed to EDCs for various exposure times. The expression of HSP90 transcripts was significantly increased in C. japonica crabs exposed to BPA and NP at different concentrations for 12, 24, 48 and 96 hours. The mRNA expression of HSP90 gene was significantly induced in a concentration- and time-dependent manner after BPA or NP exposures for 96 hours. Conclusions Taken together, expression analysis of Asian paddle crab HSP90 gene provided useful molecular information about crab responses in stress conditions and potential ways to monitor the EDCs stressors in marine environments.

• Korean Journal of Veterinary Research
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• v.57 no.2
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• pp.97-104
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• 2017

Solanum lycopersicum, commonly known as tomato, is widely used in raw, cooked, or liquid forms because it contains nutritional compounds that are beneficial for human health, including carotenoids, lycopene, ascorbic acid, vitamins, and minerals. The tomato is perhaps the most widely studied fruit, especially with respect to its cardioprotective effects. In this study, we aimed to identify the anti-inflammatory mechanisms by which the tomato elicits its anti-inflammatory properties. We treated murine macrophage RAW 264.7 cells with a tomato ethanol extract and performed various biochemical assays including nitric oxide inhibition, cell viability, RNA extraction, expression of pro-inflammatory mediators and cytokines, and immunoblotting, as well we assessed cell survival rates. Our results have shown for the first time that a tomato ethanol extract treatment can suppress nitric oxide production in a dose-dependent manner without cytotoxicity. Moreover, it inhibits the expression of pro-inflammatory mediators and cytokines and elicits its anti-inflammatory effects via the nuclear factor kappa-light-chain-enhancer of activated B cells ($NF-{\kappa}B$) and mitogen-activated protein kinase (MAPK) pathways. In addition, administration of tomato syrup potently rescued mice from septic shock induced by lipopolysaccharide injection. Collectively, our results elucidate details regarding the anti-inflammatory mechanisms of tomato.

• Journal of Plant Biotechnology
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• v.44 no.3
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• pp.287-295
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• 2017

Water temperature is one of the major factors that impacts the growth and life cycle of Pyropia tenera, one of the most valuable and cultivated marine red algae belonging to Bangiales (Rhodophytes). We analyzed transcriptome from gametophyte of P. tenera under normal and high temperature conditions, and identified four small heat shock proteins (sHSPs). They have no significant amino acid sequence homology with known proteins in public databases except PhsHSP22 from Pyropia haitanensis. PtsHSP19.3 gene responded to high temperature but slightly or not to desiccation, freezing or high salt condition. When the PtsHSP19.3 gene was overexpressed in Chlamydomonas reinhardtii, transformed Chlamydomonas lines revealed much higher growth rate than that of control cells under heat stress condition. Transformed cells also grew well in those of the control cell onto the medium containing high salt or $H_2O_2$. When the PtsHSP19.3 was fused to GFP and introduced into tobacco protoplast, fluorescence was detected at several spots. Results indicate that PtsHSP19.3 may form super-molecular assembles and be involved in tolerance to heat stress.