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1.
Endocrinology ; 164(5)2023 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-36869769

RESUMO

Fibrosis is a pathological state caused by excess deposition of extracellular matrix proteins in a tissue. Male bovine growth hormone (bGH) transgenic mice experience metabolic dysfunction with a marked decrease in lifespan and with increased fibrosis in several tissues including white adipose tissue (WAT), which is more pronounced in the subcutaneous (Sc) depot. The current study expanded on these initial findings to evaluate WAT fibrosis in female bGH mice and the role of transforming growth factor (TGF)-ß in the development of WAT fibrosis. Our findings established that female bGH mice, like males, experience a depot-dependent increase in WAT fibrosis, and bGH mice of both sexes have elevated circulating levels of several markers of collagen turnover. Using various methods, TGF-ß signaling was found unchanged or decreased-as opposed to an expected increase-despite the marked fibrosis in WAT of bGH mice. However, acute GH treatments in vivo, in vitro, or ex vivo did elicit a modest increase in TGF-ß signaling in some experimental systems. Finally, single nucleus RNA sequencing confirmed no perturbation in TGF-ß or its receptor gene expression in any WAT cell subpopulations of Sc bGH WAT; however, a striking increase in B lymphocyte infiltration in bGH WAT was observed. Overall, these data suggest that bGH WAT fibrosis is independent of the action of TGF-ß and reveals an intriguing shift in immune cells in bGH WAT that should be further explored considering the increasing importance of B cell-mediated WAT fibrosis and pathology.


Assuntos
Hormônio do Crescimento , Fator de Crescimento Transformador beta , Camundongos , Animais , Bovinos , Masculino , Feminino , Camundongos Transgênicos , Fator de Crescimento Transformador beta/metabolismo , Hormônio do Crescimento/metabolismo , Tecido Adiposo Branco , Fibrose , Tecido Adiposo/metabolismo
2.
Ann Coloproctol ; 39(3): 242-249, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35295071

RESUMO

PURPOSE: The anatomical distribution of perianal warts is associated with patient characteristics such as sexual orientation. The purpose of this study is to confirm this experiential knowledge using a quantitative classification system and analysis and to obtain findings useful for future treatment. METHODS: From January 2014 to December 2020, 93 patients with perianal warts presented to our hospital. Patients were analyzed for age, sex, lesion site, and recurrence type, among other factors. The lesion site was divided into skin (S) and anal epithelium (anoderm, A), and the number and degree of each were classified into grades 0 to 3. The higher grade between S and A determines its dominant type, such as type S (e.g., S3A1) and type A (e.g., S0A2). RESULTS: The average age of the patients was 39.6 years, and the percentage of patients who were not married was 54.8%. In all, 95.8% of patients were positive for low-risk human papillomavirus (HPV). Type S accounted for 80.6%, whereas type A accounted for 9.7%. Type A cases were all male and were all presumed to be men who have sex with men (MSM). This indicates that the determination of type A may be highly specific for MSM. The type at the time of recurrence was the same type at the time of the first surgery in almost all cases. CONCLUSION: In cases of perianal warts, it is useful to analyze the lesion by considering the range and grade separately for daily clinical practice on proctologist.

3.
Pituitary ; 25(1): 1-51, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34797529

RESUMO

Much of our understanding of GH's action stems from animal models and the generation and characterization of genetically altered or modified mice. Manipulation of genes in the GH/IGF1 family in animals started in 1982 when the first GH transgenic mice were produced. Since then, multiple laboratories have altered mouse DNA to globally disrupt Gh, Ghr, and other genes upstream or downstream of GH or its receptor. The ability to stay current with the various genetically manipulated mouse lines within the realm of GH/IGF1 research has been daunting. As such, this review attempts to consolidate and summarize the literature related to the initial characterization of many of the known gene-manipulated mice relating to the actions of GH, PRL and IGF1. We have organized the mouse lines by modifications made to constituents of the GH/IGF1 family either upstream or downstream of GHR or to the GHR itself. Available data on the effect of altered gene expression on growth, GH/IGF1 levels, body composition, reproduction, diabetes, metabolism, cancer, and aging are summarized. For the ease of finding this information, key words are highlighted in bold throughout the main text for each mouse line and this information is summarized in Tables 1, 2, 3 and 4. Most importantly, the collective data derived from and reported for these mice have enhanced our understanding of GH action.


Assuntos
Hormônio do Crescimento , Receptores da Somatotropina , Animais , Composição Corporal , Hormônio do Crescimento/genética , Hormônio do Crescimento/metabolismo , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/metabolismo , Camundongos , Camundongos Transgênicos , Modelos Animais , Receptores da Somatotropina/genética , Receptores da Somatotropina/metabolismo
4.
Mar Drugs ; 19(6)2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-34063932

RESUMO

Marine sponges are an excellent source of biologically active secondary metabolites. We focus on deep-sea sponges for our discovery study. A marine sponge Cladocroce sp. exhibited cytotoxic activity in the bioactivity screening. From this sponge a previously unreported cytotoxic glycosphingolipid, calyxoside B, was isolated and the structure of this compound was elucidated by analyses of MS and NMR spectra and chemical derivatization. We converted the ketone in the middle of a long aliphatic chain into an oxime to which was applied Beckmann rearrangement to afford two positional isomers of amides. The products were subjected to acidic hydrolysis followed by LC-MS analysis, permitting us to assign unequivocally the position of the ketone. Calyxoside B shows cytotoxicity against HeLa cells with an IC50 value of 31 µM and also weakly stimulated the production of cytokines in mice.


Assuntos
Citotoxinas/química , Glicoesfingolipídeos/química , Poríferos/química , Amidas/química , Animais , Citocinas/metabolismo , Citotoxinas/isolamento & purificação , Citotoxinas/farmacologia , Glicoesfingolipídeos/isolamento & purificação , Glicoesfingolipídeos/farmacologia , Células HeLa , Humanos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Estrutura Molecular , Estereoisomerismo
5.
J Nat Prod ; 84(6): 1848-1853, 2021 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-34081460

RESUMO

A previously unreported heterodetic cyclic peptide, homophymamide A (1), was isolated from a Homophymia sp. marine sponge. The structure of homophymamide A was determined to be a lower homologue of anabaenopeptins by spectroscopic analysis, chemical degradation, and chemical synthesis. Analysis of the acidic hydrolysate showed that the racemization of Lys took place, leading us to pose a cautionary note on the configurational assignment of peptides that contain a ureido bond.


Assuntos
Peptídeos Cíclicos/química , Poríferos/química , Animais , Japão , Estrutura Molecular
6.
Biomed Pharmacother ; 139: 111636, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33957566

RESUMO

This study was designed to reveal the protective effects of dietary supplementation of curcumin against renal cell tumours and oxidative stress induced by renal carcinogen iron nitrilotriacetate (Fe-NTA) in ddY male mice. The results showed that mice treated with a renal carcinogen, Fe-NTA, a 35% renal cell tumour incidence was noticed, whereas renal cell tumour occurrence was elevated to 80% in Fe-NTA promoted and N-diethylnitrosamine (DEN)-initiated mice as compared with saline- treated mice. No incidence of tumours has been observed in DEN-initiated non-promoted mice. Diet complemented with 0.5% and 1.0% curcumin fed prior to, during and after treatment with Fe-NTA in DEN-initiated animals, tumour incidence was reduced dose-dependently to about 45% and 30% respectively. Immunohistochemical studies also revealed the increased formation of 4-hydroxy-2-nonenal (HNE)-modified protein adducts and 8-hydroxy-2'-deoxyguanosine (8-OHdG) in kidney tissue of mice treated with an intraperitoneal injection of Fe-NTA (6.0 mg Fe/kg body weight.). Furthermore, Fe-NTA treatment of mice also resulted in significant elevation of malondialdehyde (MDA), serum urea, and creatinine and decreases renal glutathione. However, the changes in most of these parameters were attenuated dose-dependently by prophylactic treatment of animals with 0.5% and 1% curcumin diet, this may be due to its antioxidative impact of curcumin. These results suggest that intake of curcumin is beneficial for the prevention of renal cell tumours and oxidative stress damage mediated by renal carcinogen, Fe-NTA.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Antioxidantes/uso terapêutico , Carcinoma de Células Renais/induzido quimicamente , Carcinoma de Células Renais/tratamento farmacológico , Curcumina/uso terapêutico , Neoplasias Renais/induzido quimicamente , Neoplasias Renais/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , 8-Hidroxi-2'-Desoxiguanosina , Aldeídos , Animais , Anticarcinógenos/farmacologia , Nitrogênio da Ureia Sanguínea , Carcinógenos , Creatinina/sangue , Dieta , Dietilnitrosamina , Relação Dose-Resposta a Droga , Compostos Férricos , Masculino , Camundongos , Ácido Nitrilotriacético/análogos & derivados
7.
J Nat Prod ; 84(5): 1676-1680, 2021 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-33966383

RESUMO

Oshimalides A (1) and B (2) were isolated from a Luffariella sp. marine sponge. The absolute configurations of the stereogenic centers in the cyclohexenone ring were determined by the modified Mosher's analysis of the reduction product. The absolute configuration of the stereogenic center in the dihydropyran ring was assigned by analysis of the 1H NMR data of the vicinal diols which were prepared by AD-mix reagents stereoselectively.


Assuntos
Poríferos/química , Sesterterpenos/química , Animais , Organismos Aquáticos/química , Japão , Estrutura Molecular , Sesterterpenos/isolamento & purificação , Terpenos
8.
Org Lett ; 23(9): 3477-3480, 2021 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-33885313

RESUMO

Myrindole A, a bis-indole alkaloid, was isolated from the deep-sea sponge Myrmekioderma sp. The high degree of unsaturation of the molecule complicated the assignment of its structure by standard 2D-NMR experiments but was ultimately achieved by a combination of 1H-15N-HMBC and 1,n-ADEQUATE experiments as well as the comparison of measured and calculated CD spectra. Myrindole A showed antimicrobial activity against Gram-positive and Gram-negative bacteria.


Assuntos
Antibacterianos/farmacologia , Bactérias Gram-Negativas/química , Bactérias Gram-Positivas/química , Alcaloides Indólicos/química , Animais , Antibacterianos/química , Espectroscopia de Ressonância Magnética , Poríferos/química
9.
Sci Rep ; 11(1): 7368, 2021 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-33811231

RESUMO

Algal biofuel research aims to make a renewable, carbon-neutral biofuel by using oil-producing microalgae. The freshwater microalga Botryococcus braunii has received much attention due to its ability to accumulate large amounts of petroleum-like hydrocarbons but suffers from slow growth. We performed a large-scale screening of fast-growing strains with 180 strains isolated from 22 ponds located in a wide geographic range from the tropics to cool-temperate. A fast-growing strain, Showa, which recorded the highest productivities of algal hydrocarbons to date, was used as a benchmark. The initial screening was performed by monitoring optical densities in glass tubes and identified 9 wild strains with faster or equivalent growth rates to Showa. The biomass-based assessments showed that biomass and hydrocarbon productivities of these strains were 12-37% and 11-88% higher than that of Showa, respectively. One strain, OIT-678 established a new record of the fastest growth rate in the race B strains with a doubling time of 1.2 days. The OIT-678 had 36% higher biomass productivity, 34% higher hydrocarbon productivity, and 20% higher biomass density than Showa at the same cultivation conditions, suggesting the potential of the new strain to break the record for the highest productivities of hydrocarbons.


Assuntos
Clorófitas/metabolismo , Hidrocarbonetos/metabolismo , Microalgas/metabolismo , Biocombustíveis , Biomassa , Clorófitas/química , Clorófitas/crescimento & desenvolvimento , Água Doce , Ensaios de Triagem em Larga Escala , Humanos , Hidrocarbonetos/isolamento & purificação , Microalgas/química , Microalgas/crescimento & desenvolvimento , Microalgas/isolamento & purificação
10.
Bioorg Med Chem ; 28(2): 115233, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31848114

RESUMO

New sesquiterpene quinones, metachromins X (1) and Y (2), together with the known metachromins C (3), J (4), and T (5), were isolated as inhibitors of cell cycle progression in the HeLa/Fucci2 cells. The structure of 1 was assigned by spectroscopic data and confirmed by a total synthesis. The planar structure of 2 was determined by interpretation of spectroscopic data, whereas its absolute configuration was analyzed by a combination of chiral HPLC and CD spectroscopy. Metachromins X (1) and C (3) arrested the cell cycle progression of HeLa/Fucci2 cells at S/G2/M phase.


Assuntos
Antineoplásicos/farmacologia , Poríferos/química , Sesquiterpenos/farmacologia , Animais , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Humanos , Estrutura Molecular , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Relação Estrutura-Atividade , Células Tumorais Cultivadas
11.
Sci Rep ; 9(1): 16974, 2019 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-31740707

RESUMO

The green microalga Botryococcus braunii produces hydrocarbon oils at 25-75% of its dry weight and is a promising source of biofuel feedstock. Few studies have examined this species' ecology in natural habitats, and few wild genetic resources have been collected due to difficulties caused by its low abundance in nature. This study aimed to develop a real-time PCR assay for specific detection and quantification of this alga in natural environments and to quantify spatiotemporal variations of wild B. braunii populations in a tropical pond. We designed PCR primers toward the hydrocarbon biosynthesis gene SSL-3 and examined amplification specificity and PCR efficiency with 70 wild strains newly isolated from various environments. The results demonstrated that this PCR assay specifically amplified B. braunii DNA, especially that of B-race strains, and can be widely used to detect wild B. braunii strains in temperate and tropical habitats. Field-testing in a tropical pond suggested a diurnal change in the abundance of B. braunii in surface water and found B. braunii not only in surface water, but also at 1-1.5 m deep and in bottom sediments. This method can contribute to efficient genetic resource exploitations and may also help elucidate the unknown ecology of B. braunii.


Assuntos
Proteínas de Algas/metabolismo , Clorófitas/metabolismo , Água Doce/microbiologia , Hidrocarbonetos/metabolismo , Microalgas/metabolismo , Óleos/metabolismo , Proteínas de Algas/genética , Biocombustíveis , Vias Biossintéticas/genética , Clorófitas/classificação , Clorófitas/genética , Ecossistema , Amplificação de Genes , Geografia , Indonésia , Japão , Microalgas/classificação , Microalgas/genética , Filogenia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Clima Tropical
12.
Cancers (Basel) ; 11(9)2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31547367

RESUMO

Growth hormone (GH) facilitates therapy resistance in the cancers of breast, colon, endometrium, and melanoma. The GH-stimulated pathways responsible for this resistance were identified as suppression of apoptosis, induction of epithelial-to-mesenchymal transition (EMT), and upregulated drug efflux by increased expression of ATP-binding cassette containing multidrug efflux pumps (ABC-transporters). In extremely drug-resistant melanoma, ABC-transporters have also been reported to mediate drug sequestration in intracellular melanosomes, thereby reducing drug efficacy. Melanocyte-inducing transcription factor (MITF) is the master regulator of melanocyte and melanoma cell fate as well as the melanosomal machinery. MITF targets such as the oncogene MET, as well as MITF-mediated processes such as resistance to radiation therapy, are both known to be upregulated by GH. Therefore, we chose to query the direct effects of GH on MITF expression and activity towards conferring chemoresistance in melanoma. Here, we demonstrate that GH significantly upregulates MITF as well as the MITF target genes following treatment with multiple anticancer drug treatments such as chemotherapy, BRAF-inhibitors, as well as tyrosine-kinase inhibitors. GH action also upregulated MITF-regulated processes such as melanogenesis and tyrosinase activity. Significant elevation in MITF and MITF target gene expression was also observed in mouse B16F10 melanoma cells and xenografts in bovine GH transgenic (bGH) mice compared to wild-type littermates. Through pathway inhibitor analysis we identified that both the JAK2-STAT5 and SRC activities were critical for the observed effects. Additionally, a retrospective analysis of gene expression data from GTEx, NCI60, CCLE, and TCGA databases corroborated our observed correlation of MITF function and GH action. Therefore, we present in vitro, in vivo, and in silico evidence which strongly implicates the GH-GHR axis in inducing chemoresistance in human melanoma by driving MITF-regulated and ABC-transporter-mediated drug clearance pathways.

13.
Bioresour Technol ; 291: 121911, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31383389

RESUMO

Botryococcus braunii is known for its high yield of extracellular hydrocarbons and polysaccharides. Hydrocarbons, especially botryococcenes and squalene can be used as not only fuels but also alternative feedstock for other fossil-based products. Exopolysaccharides excreted from B. braunii can be used as scaffolds for polyesters production, and have a notable potential for synthesis of nanoparticles. B. braunii is also a rich source of carotenoids, especially the unique secondary carotenoids such as botryoxanthins that have never been found in other microalgae. The morphology, physiology, and outer cell walls of B. braunii are complex. Understanding the colony structure shall provide insights into the mechanism of cell growth and chemicals secretion. It is possible to improve the production economics of the alga with advanced culture systems. Moreover, investigation of metabolic pathways for B. braunii may help us understand their regulation and provide valuable information for strain selection and optimal production of high-value chemicals.


Assuntos
Clorófitas , Microalgas , Carotenoides , Hidrocarbonetos , Esqualeno
14.
Biosci Biotechnol Biochem ; 83(11): 1985-1988, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31250707

RESUMO

N6-Isopentenyladenosine (i6A) was isolated from a marine sponge Oceanapia sp. as the major cytotoxic constituent along with N6-isopentenyladenosine 5'-monophosphate (i6AP) which was inactive. The structures of i6A and i6AP were assigned by a combination of the analysis of NMR spectroscopy and mass spectrometry. This is the first isolation of i6A and i6AP from a marine sponge.


Assuntos
Isopenteniladenosina/química , Isopenteniladenosina/isolamento & purificação , Poríferos/química , Animais , Modelos Moleculares , Conformação Molecular
15.
J Nat Prod ; 81(11): 2595-2599, 2018 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-30346758

RESUMO

There are several examples of marine organisms whose metabolic profiles differ among conspecifics inhabiting the same region. We have analyzed the metabolic profile of each colony of a Theonella swinhoei marine sponge with a yellow interior and noticed the patchy distribution of one metabolite. This compound was isolated and its structure was studied by a combination of spectrometric analyses and chemical degradation, showing it to be a congener in the theonellamide class of bicyclic peptides. Theonellamides had previously been isolated by us only from T. swinhoei with a white interior and not from those with a yellow interior.


Assuntos
Peptídeos Cíclicos/isolamento & purificação , Theonella/química , Animais , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Humanos , Estrutura Molecular , Peptídeos Cíclicos/química
16.
J Plant Res ; 131(5): 839-848, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29725892

RESUMO

The B race of a green microalga Botryococcus braunii Kützing produces triterpene hydrocarbons that is a promising source for biofuel. In this algal race, precursors of triterpene hydrocarbons are provided from the 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway. The terminal enzyme of this pathway, 4-hydroxy-3-methylbut-2-enyl diphosphate reductase (HDR) is regarded as one of the key enzymes that affect yields of products in terpene biosynthesis. In order to better understand the MEP pathway of the alga, cDNA and genomic clones of HDR were obtained from B. braunii Showa strain. B. braunii HDR (BbHDR) is encoded on a single copy gene including a 1509-bp open reading frame that was intervened by 6 introns. The exon-intron structure of BbHDR genes did not show clear relation to phylogeny, while its amino acid sequence reflected phyla and classes well. BbHDR sequence was distinctive from that of the HDR protein from Escherichia coli in the residues involved in hydrogen-bond network that surrounds substrate. Introduction of BbHDR cDNA into an E. coli HDR deficient mutant resulted in recovery of its auxotrophy. BbHDR expression level was upregulated from the onset of liquid culture to the 24th day after inoculation with a 2.5-fold increase and retained its level in the subsequent period.


Assuntos
Proteínas de Algas/metabolismo , Clorófitas/enzimologia , Eritritol/análogos & derivados , Hidrocarbonetos/metabolismo , Oxirredutases/metabolismo , Fosfatos Açúcares/metabolismo , Proteínas de Algas/genética , Sequência de Aminoácidos , Clorófitas/genética , Clonagem Molecular , DNA Complementar/genética , Eritritol/metabolismo , Escherichia coli/enzimologia , Escherichia coli/genética , Fases de Leitura Aberta/genética , Oxirredutases/genética , Filogenia , Triterpenos/metabolismo
17.
J Nat Prod ; 81(5): 1295-1299, 2018 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-29701963

RESUMO

Poecillastrin H (1), a chondropsin-type macrolide with a conjugated pentaene moiety, was isolated from the Characella sp. marine sponge. The planar structure of 1 was elucidated by analysis of spectroscopic data. The absolute configuration of the ß-hydroxyaspartic acid residue (ß-OHAsp) was determined to be d- threo by Marfey's analysis, and the mode of lactone ring formation through the OHAsp residue was determined by chemical degradation. Poecillastrin H was extremely sensitive toward light and showed potent cytotoxic activity against 3Y1 cells with an IC50 value of 4.1 nM.


Assuntos
Macrolídeos/química , Poríferos/química , Animais , Linhagem Celular , Citotoxinas/química , Lactonas/química , Ratos
18.
J Nat Prod ; 81(4): 1108-1112, 2018 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-29613787

RESUMO

Morphology-guided cell-based screening of the extract of a Mycale sp. marine sponge led to the isolation of two trisoxazole macrolides, miuramides A (1) and B (2), which induced characteristic morphological changes in 3Y1 cells. The structure of 1 including absolute configuration was elucidated by a combination of the analysis of spectroscopic data, derivatization, and degradation. Both compounds exhibit potent cytotoxicity against 3Y1 cells.


Assuntos
Macrolídeos/química , Macrolídeos/farmacologia , Oxazóis/química , Oxazóis/farmacologia , Poríferos/química , Animais , Linhagem Celular , Citotoxinas/química , Citotoxinas/farmacologia , Mamíferos , Fenótipo , Ratos
19.
Mar Drugs ; 16(2)2018 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-29466301

RESUMO

Three new polyketides, lactomycins A (1)-C (3), were isolated from the culture broth of a marine-derived Streptomyces sp. ACT232 as cathepsin B inhibitors. Their structures were determined by a combination of NMR and MS data analyses to be the dephosphorylated derivatives of a phoslactomycin class of metabolites. Lactomycins exhibited cathepsin B inhibitory activity (IC50 0.8 to 4.5 µg/mL). Even though the biosynthetic gene clusters found in the genome of the current strain have high similarity to those of phoslactomycin, neither phoslactomycins nor leustroducsins were detected by LC-MS analyses of the crude extract.


Assuntos
Catepsina B/química , Streptomyces/química , Antifúngicos/química , Indóis/química , Espectroscopia de Ressonância Magnética/métodos , Naftoquinonas/química , Policetídeos/química
20.
Plant Biotechnol (Tokyo) ; 35(3): 297-301, 2018 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31819737

RESUMO

The green microalga Botryococcus braunii Showa, which produces large amounts of triterpene hydrocarbons, exclusively uses the 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway for isoprenoid biosyntheses, and the terminal enzyme in this pathway, 4-hydroxy-3-methylbut-2-enyl diphosphate reductase (HDR), is regarded as a light-dependent key regulatory enzyme. In order to investigate the possible association of HDR and ferredoxin in this organism, we constructed tertiary structure models of B. braunii HDR (BbHDR) and one of ferredoxin families in the alga, a photosynthetic electron transport F (BbPETF)-like protein, by using counterparts from E. coli and Chlamydomonas reinhardtii as templates, respectively, and performed docking analysis of these two proteins. After docked models are superimposed onto their counterpart proteins in a non-photosynthetic organism, Plasmodium falciparum, the BbPETF-like protein comes in contact with the backside of BbHDR, which was defined in a previous report (Rekittke et al. 2013), and the distance of the two Fe-S centers is 14.7 Å. This distance is in almost the same level as that for P. falicarum, 12.6 Å. To our knowledge, this is the first model suggesting the possible association of HDR with a ferredoxin in O2-evolving photosynthetic organisms.

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