• Proceedings of the Korean Society of Applied Pharmacology
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• 2002.07a
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• pp.113-113
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• 2002

Phylogenetically conserved Bcl-2 family proteins play a pivotal role in the regulation of apoptosis from virus to human. Members of the Bcl-2 family consist of antiapoptotic proteins such as Bcl-2, Bcl-xL, and Bcl-w, and proapoptotic proteins such as BAD, Bax, BOD, and Bok. It has been proposed that anti- and proapoptotic Bcl-2 proteins regulate cell death by binding to each other and forming heterodimers. A delicate balance between anti- and proapoptotic Bcl-2 family members exists in each cell and the relative concentration of these two groups of proteins determines whether the cell survives or undergoes apoptosis. Mcl-1 (Myeloid cell :leukemia-1) is a member of the Bcl-2 family proteins and was originally cloned as a differentiation-induced early gene that was activated in the human myeloblastic leukemia cell line, ML-1 . Mcl-1 is expressed in a wide variety of tissues and cells including neoplastic ones. We recently identified a short splicing variant of Mcl-1 short (Mcl-IS) and designated the known Mcl-1 as Mcl-1 long (Mcl-lL). Mcl-lL protein exhibits antiapoptotic activity and possesses the BH (Bcl-2 homology) 1, BH2, BH3, and transmembrane (TM) domains found in related Bcl-2 proteins. In contrast, Mcl-1 S is a BH3 domain-only proapoptotic protein that heterodimerizes with Mcl-lL. Although both Mc1-lL and Mcl-lS proteins contain BH domains fecund in other Bcl-2 family proteins, they are distinguished by their unusually long N-terminal sequences containing PEST (proline, glutamic acid, serine, and threonine) motifs, four pairs of arginine residues, and alanine- and glycine-rich regions. In addition, the expression pattern of Mcl-1 protein is different from that of Bcl-2 suggesting a unique role (or Mcl-1 in apoptosis regulation. Tankyrasel (TRF1-interacting, ankyrin-related ADP-related polymerasel) was originally isolated based on its binding to TRF 1 (telomeric repeat binding factor-1) and contains the sterile alpha motif (SAM) module, 24 ankyrin (ANK) repeats, and the catalytic domain of poly(adenosine diphosphate-ribose) polymerase (PARP). Previous studies showed that tankyrasel promotes telomere elongation in human cells presumably by inhibiting TRFI though its poly(ADP-ribosyl)action by tankyrasel . In addition, tankyrasel poly(ADP-ribosyl)ates Insulin-responsive amino peptidase (IRAP), a resident protein of GLUT4 vesicles, and insulin stimulates the PARP activity of tankyrase1 through its phosphorylation by mitogen-activated protein kinase (MAPK). ADP-ribosylation is a posttranslational modification that usually results in a loss of protein activity presumably by enhancing protein turnover. However, little information is available regarding the physiological function(s) of tankyrase1 other than as a PARP enzyme. In the present study, we found tankyrasel as a specific-binding protein of Mcl-1 Overexpression of tankyrasel led to the inhibition of both the apoptotic activity of Mel-lS and the survival action of Mcl-lL in mammalian cells. Unlike other known tankyrasel-interacting proteins, tankyrasel did not poly(ADP-ribosyl)ate either of the Mcl-1 proteins despite its ability to decrease Mcl-1 proteins expression following coexpression. Therefore, this study provides a novel mechanism to regulate Mcl-1-modulated apoptosis in which tankyrasel downregulates the expression of Mcl-1 proteins without the involvement of its ADP-ribosylation activity.

• Development and Reproduction
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• v.12 no.3
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• pp.297-303
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• 2008

BCL-2 family members are essential protein for the regulation of cell death and survival consisting both antiapoptotic and pro-apoptotic proteins. In the present study, we designed and cloned a new apoptotic molecule MCL-1ES BH3M coding a modified protein of MCL-1L. Compared to MCL-1L protein, MCL-1ES BH3M lacks the PEST motifs known to be involved in MCL-1L protein degradation and has seven mutated residues in BH3 domain critical for dimerization with BCL-2 family members. Overexpression of MCL-1ES BH3M induced death of different cells, and its cell killing effect was not blocked by forced expression of the pro-survival protein MCL-1L. Expression of MCL-1ES BH3M protein led to the activation of caspase 9 and caspase 3, suggesting apoptotic cell death, and confocal fluorescent microscopic analyses showed that MCL-1ES BH3M was partially localized in mitochondria. In conclusion, we reported a new apoptotic molecule and determined its cell death activity in cells.

• Journal of Life Science
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• v.31 no.1
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• pp.90-99
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• 2021

In this study, to reduce the production cost of poly(3-hydroxyalkanoates) (PHA), optimal cell growth and PHA biosynthesis conditions of the isolated strain Pseudomonas sp. EML8 were established using waste frying oil (WFO) as the cheap carbon source. Gas chromatography (GC) and GC mass spectrometry analysis of the medium-chain-length PHA (mcl-PHAWFO) obtained by Pseudomonas sp. EML8 of WFO indicated that it was composed of 7.28 mol% 3-hydrxoyhexanoate, 39.04 mol% 3-hydroxyoctanoate, 37.11 mol% 3-hydroxydecanoate, and 16.58 mol% 3-hydroxvdodecanoate monomers. When Pseudomonas sp. EML8 were culture in flask, the maximum dry cell weight (DCW) and the mcl-PHAWFO yield (g/l) were showed under WFO (20 g/l), (NH4)2SO4 (0.5 g/l), pH 7, and 25℃ culture conditions. Based on this, the highest DCW, mcl-PHAWFO content, and mcl-PHAWFO yield from 3-l-jar fermentation was obtained after 48 hr. Similar results were obtained using 20 g/l of fresh frying oil (FFO) as a control carbon source. In this case, the DCW, the mcl-PHAFFO content, and the mcl-PHAFFO yields were 2.7 g/l, 62 wt%, and 1.6 g/l, respectively. Gel permeation chromatography analysis confirmed the average molecular weight of the mcl-PHAWFO and mcl-PHAFFO to be between 165-175 kDa. Thermogravimetric analysis showed decomposition temperature values of 260℃ and 274.7℃ for mcl-PHAWFO and mcl-PHAFFO, respectively. In conclusion, Pseudomonas sp. EML8 and WFO could be suggested as a new candidate and substrate for the industrial production of PHA.

• Journal of the Korean Chemical Society
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• v.38 no.11
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• pp.808-818
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• 1994

The neutral compounds [$MCl_3L_2$(MeCN)] (M = Mo, V: L = $PPh_3$, 1/2 phda) have been prepared from the reaction of starting material $MCl_z$ (M = Mo; z = 5, M = V; z = 3) with N,P-donating ligands in acetonitrile solution. Addition of $AgClO_4$ to these neutral monomeric compounds in acetone solution were produced [$MCl_3-_nL_2(MeCN)(S)_n$]$(ClO_4)_n$ (n = 1, 2 : s = solvent). Finally treatment of bivalent cationic compound and neutral compound was formed chloride bridged dinuclear complex $[(MeCN)(L)_2ClM({\mu}-Cl)_2M'Cl(L)_2(MeCN)](ClO_4)_2$ and treatment of univalent cationic compound with half equivalent pyrazine to pyrazine bridged complex $[(MeCN)(L)_2Cl_2M({\mu}-pyz)M'Cl_2(L)_2(MeCN)](ClO_4)_2$. These complexes are characterized by elemental analysis, $^1H$, $^{13}C$ NMR, IR, Far-IR and UV-Vis spectroscopy.

• Journal of the Korean Chemical Society
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• v.39 no.7
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• pp.530-537
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• 1995

The neutral complexes $MCl_3(phda)(MeCN)]$ and $[MCl_3(PPh_3)_2(MeCN)]$ (M=Mo, V) were prepared by the reaction of $MCl_z$, (M=Mo; z=5, M=V; z=3) with N, P-donating ligands in acetonitrile solution. Addition of AgClO_4$ to these neutral monomeric complexes in acetone solution afforded $MCl_{3-n}L_2(MeCN)(S)_n](ClO_4)_n$ (n=1, 2 : s=solvent). Two types of asymmetrical homo- and hetero-dinuclear complexes have been synthesized. The type of chloride bridged dinuclear complex is $[(MeCN)(phda)ClM({\mu}-Cl)_2M'Cl(PPh_3)_2(MeCN)](ClO_4)_2.$ And the type of pyrazine bridged complex is $[(MeCN)(phda)Cl_2M({\mu}-pyz)M'Cl_2(PPh_3)_2(MeCN)](ClO_4)_2.$ These complexes were characterized by elemental analysis, $^1H,\;^13C$ NMR, IR, Far-IR and UV-Vis spectroscopy.

• Food Science of Animal Resources
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• v.32 no.5
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• pp.635-643
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• 2012

As an appraisal for the application of a new starter culture, more than 200 lactic acid bacteria strains were isolated from raw milk and healthy human feces. The strains showing excellent growth and acid production ability in 10% skim milk media were selected and identified as Lactobacillus casei based on the results of their API carbohydrate fermentation patterns, as well as 16S rDNA sequence analysis. To assess the effect of L. casei strains on irritable bowel disease (IBD), the inhibitory effect of the selected strains against the nitric oxide (NO) production of lipopolysaccharide (LPS)-stimulated RAW 264.7 cells was measured. Among the tested L. casei strains, L. casei MCL was observed to have the greatest NO inhibitory activity. Additionally, L. casei MCL was found to inhibit mRNA expression of pro-inflammatory cytokines (interleukin-$1{\beta}$, IL-6, TNF-${\alpha}$), as well as cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) involved in pathophysiologic processes such as inflammation. The mRNA expression of anti-inflammatory cytokines, including IL-10 and transforming growth factor-$1{\beta}$ (TGF-${\beta}$) of L. casei MCL, was confirmed using quantitative real-time PCR. In conclusion, L. casei MCL showed decreases in the expression of pro-inflammatory cytokines and up-regulated expression of the anti-inflammatory cytokine.

• Microbiology and Biotechnology Letters
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• v.32 no.2
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• pp.123-127
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• 2004

Pseudomonas sp. MBEL21 was newly isolated from soil samples and found to accumulate medium-chain-length Polyhydroxyalkanoates(MCL-PHAs) using oleic acid as a sole carbon source. Among the various nutrient limiting conditions examined, including nitrogen, sulfur and phosphorus, only phosphorus limitation supported the accumulation of MCL-PHAs up to 15 wt％ of dry cell weight in flask cultures. MCL-PHAs produced by Pseudomonas sp. MBEL21 was mainly composed of 3-hydroxy-5-cis-tetradecenoate. Fed-batch culture of Pseudomonas sp. MBEL21 by novel feeding strategies based on cell growth charcteristics was carried out under phosphorus limitation using oleic acid as a sole carbon source. The final cell concentration and PHA content of 82 g/L and 28 wt％, respectively, were obtained. Furthermore, PHA consisted of MCL-hydroxyalkanoates and 3-hydroxybutyrate could be produced using olive oil as a sole carbon source.

• Korean Journal of Microbiology
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• v.48 no.3
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• pp.200-206
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• 2012

A bacterial strain capable of synthesizing polyhydroxyalkanoates (PHAs) with an unusual pattern of monomer units was isolated from activated sludge using the enrichment culture technique. The organism, identified as Pseudomonas aeruginosa P-5, produced polyesters consisting of 3-hydroxyvalerate and medium-chain-length (MCL) 3-hydroxyalkanoate monomer units when $C_{-odd}$ alkanoic acids such as nonanoic acid and heptanoic acid were fed as the sole carbon source. Solvent fractionation experiments using chloroform and hexane revealed that the 3-hydroxyalkanoate monomer units in these polyesters were copolymerized. The molar concentration of 3-hydroxyvalerate in the polyesters produced were significantly elevated up to 26 mol% by adding 1.0 g/L valeric acid as the cosubstrate. These copolyesters were sticky with low degrees of crystallinity. The PHA synthase genes were cloned, and the deduced amino acid sequences were determined. P. aeruginosa P-5 possessed genes encoding MCL-PHA synthases (PhaC1 and PhaC2) but lacked the short-chain-length PHA synthase gene, suggesting that the MCL-PHA synthases from P. aeruginosa P-5 are uniquely active for polymerizing (R)-3-hydroxyvaleryl-CoA as well as MCL (R)-3-hydroxyacyl-CoAs.

• Korean Journal of Microbiology
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• v.41 no.3
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• pp.225-231
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• 2005

The characteristics of cell growth and medium-chain-length polyhydroxyalkanoate (MCL-PHA) biosynthesis of Pseudomonas chlororaphis HS21 were investigated using plant oils as the carbon substrate. The organism was efficiently capable of utilizing plant oils, such as palm oil, corn oil, and sunflower oil, as the sole carbon source for growth and MCL-PHA production. When palm oil (5 g/L) was used as the carbon source, the cell growth and MCL-PHA accumulation of this organism occurred simultaneously, and a high dry cell weight (2.4 g/L) and MCL-PHA ($40.2\;mol{\%}$ of dry cell weight) was achieved after 30 hr of batch-fermentation. The repeating unit in the MCL-PHA produced from palm oil composed of 3-hydroxyhexanoate ($7.0\;mol{\%}$), 3-hydroxyoctanoate ($45.3\;mol{\%}$), 3-hydroxydecanoate ($39.0\;mol{\%}$), 3-hydroxydodecanoate ($6.8\;mol{\%}$), and 3-hydroxytetradecanoate ($1.9\;mol{\%}$), as determined by GC/MS. Even though glucose was a carbon substrate that support cell growth but not PHA production, the conversion rate of palm oil to PHA was significantly increased when glucose was fed as a cosubstrate, suggesting that bioconversion of some functionalized carbon substrates to related polymers in P chlororaphis HS21 could be enhanced by the co-feed of good carbon substrates for cell growth. In addition, the change of compositions of repeating units in MCL-PHAs synthesized from the plant oils was markedly affected by the supplementation of acrylic acid, an inhibitor of fatty acid ${\beta}-oxidation$. The addition of acrylic acid resulted in the increase of longer chain-length repeating units, such as 3-hydroxydodecanoate and 3-hydroxytetradecanoate, in the MCL-PHAs produced. Particularly, MCI-PHAs containing high amounts of unsaturated repeating units could be produced when sunflower oil and corn oil were used as the carbon substrate. These results suggested that the alteration of PHA synthesis pathway by acrylic acid addition can offer the opportunity to design new functional MCL-PHAs and other unusual polyesters that have unique physico-chemical properties.

• Journal of Microbiology and Biotechnology
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• v.22 no.3
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• pp.371-377
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• 2012

The present study describes medium-chain-length polyhydroxyalkanoates (mcl-PHAs) production by the Pseudomonas Gl01 strain isolated from mixed microbial communities utilized for PHAs synthesis. A two-step fed-batch fermentation was conducted with glucose and waste rapeseed oil as the main carbon source for obtaining cell growth and mcl-PHAs accumulation, respectively. The results show that the Pseudomonas Gl01 strain is capable of growing and accumulating mcl-PHAs using a waste oily carbon source. The biomass value reached 3.0 g/l of CDW with 20% of PHAs content within 48 h of cultivation. The polymer was purified from lyophilized cells and analyzed by gas chromatography (GC). The results revealed that the monomeric composition of the obtained polyesters depended on the available substrate. When glucose was used in the growth phase, 3-hydroxyundecanoate and 3-hydroxydodecanoate were found in the polymer composition, whereas in the PHAs-accumulating stage, the Pseudomonas Gl01 strain synthesized mcl-PHAs consisting mainly of 3-hydroxyoctanoate and 3-hydroxydecanoate. The transcriptional analysis using reverse-transcription real-time PCR reaction revealed that the phaC1 gene could be transcribed simultaneously to the phaZ gene.