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2.
Echocardiography ; 38(4): 701-704, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33728709

RESUMO

A 50-year-old patient presented with a stroke. An ascending aortic mass noted by computed tomography was attached to the aortic wall and was found to be thrombus at surgery. Pathologic examination revealed an intraluminal thrombus attached to a focal segment of intimal fragmentation. Sectioning of the aortic wall revealed what were findings consistent with what would be noted with a previously unrecognized traumatic ascending aortic deceleration injury. To our knowledge, this is the first case of a late presentation of deceleration aortic injury, presenting with a thrombus within the ascending aorta.


Assuntos
Doenças da Aorta , Trombose , Aorta/diagnóstico por imagem , Doenças da Aorta/diagnóstico por imagem , Doenças da Aorta/etiologia , Desaceleração , Humanos , Pessoa de Meia-Idade , Trombose/diagnóstico por imagem , Trombose/etiologia , Tomografia Computadorizada por Raios X
4.
Med Oncol ; 35(12): 152, 2018 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-30291535

RESUMO

We have previously demonstrated a significant correlative relationship between PTEN deletion and ERG rearrangement, both in the development of clinically localized prostate cancers and metastases. Herein, we evaluate the cooperative role of ERG and PTEN in oncological outcomes after radical prostatectomy for clinically localized prostate cancer. We evaluated ERG and PTEN status using three previously described cohorts. The first cohort included 235 clinically localized prostate cancer cases represented on tissue microarrays (TMA), evaluated using previously validated FISH assays for ERG and PTEN. The second cohort included 167 cases of clinically localized prostate cancer on TMAs evaluated for PTEN by FISH, and for PTEN and ERG by dual IHC. The third cohort comprised 59 clinically localized prostate cancer cases assessed by array comparative genomic hybridization (aCGH). Kaplan-Meir plots and long rank tests were used to assess the association of ERG and PTEN status with biochemical recurrence after radical prostatectomy for clinically localized prostate cancer. Of the 317 cases eligible for analyses with evaluable ERG and PTEN status, 88 (27.8%) patients developed biochemical recurrence over a median follow-up of 5.7 years. Overall, 45% (142/317) of cases demonstrated ERG rearrangement and 20% (62/317) of cases demonstrated PTEN loss. Hemizygous and homozygous deletion of PTEN was seen in 10% (18/175) and 3% (5/175) of ERG-negative cases, respectively. In contrast, hemizygous and homozygous deletion of PTEN was seen in 11% (15/142) and 17% (24/123) of ERG-positive cases, respectively. PTEN loss (heterozygous or homozygous) was significantly associated with shorter time to biochemical recurrence compared to no PTEN loss (p < 0.001). However, ERG rearrangement versus no rearrangement was not associated with time to PSA recurrence (p = 0.15). Patients who exhibited ERG rearrangement and loss of PTEN had no significant difference in time to recurrence compared to patients with wild-type ERG and loss of PTEN (p = 0.30). Our findings confirm a mutual cooperative role of ERG and PTEN in the pathogenesis of prostate cancer, particularly for homozygous PTEN deletion. ERG did not stratify outcome either alone or in combination with PTEN in this cohort.


Assuntos
Biomarcadores Tumorais/genética , Recidiva Local de Neoplasia/genética , PTEN Fosfo-Hidrolase/genética , Neoplasias da Próstata/genética , Idoso , Estudos de Coortes , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/cirurgia , Prognóstico , Prostatectomia , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia , Taxa de Sobrevida , Regulador Transcricional ERG/genética
5.
Biomark Insights ; 12: 1177271917695810, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28469398

RESUMO

High-throughput genotyping has enabled discovery of genetic variants associated with an increased risk of developing prostate cancer using genome-wide association studies (GWAS). The goal of this study was to associate GWAS information of patients with primary organ-confined and metastatic prostate cancer using gene expression data and to identify molecular networks and biological pathways enriched for genetic susceptibility variants involved in the 2 disease states. The analysis revealed gene signatures for the 2 disease states and a gene signature distinguishing the 2 patient groups. In addition, the analysis revealed molecular networks and biological pathways enriched for genetic susceptibility variants. The discovered pathways include the androgen, apoptosis, and insulinlike growth factor signaling pathways. This analysis established putative functional bridges between GWAS discoveries and the biological pathways involved in primary organ-confined and metastatic prostate cancer.

6.
J La State Med Soc ; 168(2): 71-3, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27383862

RESUMO

A 48-year-old female presented to her physician complaining of intermittent lower abdominal pain radiating to the right lower back. At the time of presentation, she was afebrile and denied any urinary symptoms such as dysuria, frequency or urgency. Physical exam was unremarkable, other than obesity, and her abdominal exam was noncontributory. Medical history, however, was notable for recurrent, Proteus mirabilis culture-proven urinary tract infections requiring antibiotic treatment for the prior three years along with hypertension, uterine fibroids post hysterectomy, diabetes and asthma. Complete blood count was within normal limits, and urine dipstick showed 1+ blood, 1+ protein and 2+ leukocytes. Full renal function labs, urine cytology, radioisotope renography and abdominopelvic CT scanning with contrast were all ordered and a laparoscopic right nephrectomy was recommended based on the results. The bisected right kidney is shown below in Figure 1. She was discharged home on post-operative day one and her follow up urology appointments indicate resolution of both her urinary tract infections and her abdominal pain.


Assuntos
Dor Abdominal/etiologia , Infecções Urinárias/etiologia , Urolitíase/complicações , Urolitíase/patologia , Feminino , Humanos , Laparoscopia , Pessoa de Meia-Idade , Nefrectomia , Urolitíase/cirurgia
7.
Microb Cell Fact ; 12: 43, 2013 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-23638724

RESUMO

BACKGROUND: Many proteins and peptides have been used in therapeutic or industrial applications. They are often produced in microbial production hosts by fermentation. Robust protein production in the hosts and efficient downstream purification are two critical factors that could significantly reduce cost for microbial protein production by fermentation. Producing proteins/peptides as inclusion bodies in the hosts has the potential to achieve both high titers in fermentation and cost-effective downstream purification. Manipulation of the host cells such as overexpression/deletion of certain genes could lead to producing more and/or denser inclusion bodies. However, there are limited screening methods to help to identify beneficial genetic changes rendering more protein production and/or denser inclusion bodies. RESULTS: We report development and optimization of a simple density gradient method that can be used for distinguishing and sorting E. coli cells with different buoyant densities. We demonstrate utilization of the method to screen genetic libraries to identify a) expression of glyQS loci on plasmid that increased expression of a peptide of interest as well as the buoyant density of inclusion body producing E. coli cells; and b) deletion of a host gltA gene that increased the buoyant density of the inclusion body produced in the E. coli cells. CONCLUSION: A novel density gradient sorting method was developed to screen genetic libraries. Beneficial host genetic changes could be exploited to improve recombinant protein expression as well as downstream protein purification.


Assuntos
Escherichia coli/metabolismo , Corpos de Inclusão/metabolismo , Centrifugação com Gradiente de Concentração , Escherichia coli/genética , Escherichia coli/crescimento & desenvolvimento , Proteínas de Escherichia coli/genética , Técnicas de Inativação de Genes , Biblioteca Gênica , Loci Gênicos , Povidona/química , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Dióxido de Silício/química
8.
Mod Pathol ; 26(6): 835-48, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23348902

RESUMO

Identification of new molecular markers has led to the molecular classification of prostate cancer based on driving genetic lesions. The translation of these discoveries for clinical use necessitates the development of simple, reliable and rapid detection systems to screen patients for specific molecular aberrations. We developed two dual-color immunohistochemistry-based assays for the simultaneous assessment of ERG-PTEN and ERG-SPINK1 in prostate cancer. A total of 232 cases from 184 localized and 48 metastatic prostate cancers were evaluated for ERG-PTEN and 284 cases from 228 localized and 56 metastatic prostate cancers were evaluated for ERG-SPINK1. Of the 232 cases evaluated for ERG-PTEN, 81 (35%) ERG-positive and 77 (33%) PTEN-deleted cases were identified. Of the 81 ERG-positive cases, PTEN loss was confirmed in 35 (15%) cases by fluorescence in situ hybridization (FISH). PTEN status was concordant in 203 cases (sensitivity 90% and specificity 87%; P<0.0001) by both immunohistochemisty and FISH; however, immunohistochemisty could not distinguish between heterozygous and homozygous deletion status of PTEN. Of the 284 cases evaluated for ERG-SPINK1, 111 (39%) cases were positive for ERG. In the remaining 173 ERG-negative cases, SPINK1 was positive in 26 (9%) cases. SPINK1 expression was found to be mutually exclusive with ERG expression; however, we identified two cases, of which one showed concomitant expression of ERG and SPINK1 in the same tumor foci, and in the second case ERG and SPINK1 were seen in two independent foci of the same tumor nodule. Unlike the homogenous ERG staining in cancer tissues, heterogeneous SPINK1 staining was observed in the majority of the cases. Further studies are required to understand the molecular heterogeneity of cases with concomitant ERG-SPINK1 expression. Automated dual ERG-PTEN and ERG-SPINK1 immunohistochemisty assays are simple, reliable and portable across study sites for the simultaneous assessment of these proteins in prostate cancer.


Assuntos
Biomarcadores Tumorais/análise , Carcinoma/química , Proteínas de Transporte/análise , Imuno-Histoquímica , Proteínas de Fusão Oncogênica/análise , PTEN Fosfo-Hidrolase/análise , Neoplasias da Próstata/química , Transativadores/análise , Biomarcadores Tumorais/genética , Carcinoma/secundário , Deleção de Genes , Heterozigoto , Homozigoto , Humanos , Hibridização in Situ Fluorescente , Masculino , Proteínas de Fusão Oncogênica/genética , PTEN Fosfo-Hidrolase/genética , Valor Preditivo dos Testes , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Análise Serial de Tecidos , Regulador Transcricional ERG , Inibidor da Tripsina Pancreática de Kazal
9.
J Urol ; 189(2): 441-6, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23253955

RESUMO

PURPOSE: We assess the accuracy of a biopsy directed treatment algorithm in correctly assigning active surveillance vs treatment in patients with small renal masses by comparing biopsy results with final surgical pathology. MATERIALS AND METHODS: From 1999 to 2011, 151 patients with small renal masses 4 cm or smaller underwent biopsy and subsequent surgical excision. Biopsy revealed cell type and grade in 133 patients, allowing the hypothetical assignment of surveillance vs treatment using an algorithm incorporating small renal mass size and histological risk group. We compared the biopsy directed management recommendation with the ideal management as defined by final surgical pathology. RESULTS: Biopsy called for surveillance of 36 small renal masses and treatment of 97 small renal masses. Final pathology showed 11 patients initially assigned to surveillance should have been assigned to treatment (8.3% of all patients, 31% of those recommended for surveillance), whereas no patients moved from treatment to surveillance. Agreement between biopsy and final pathology was 92%. Using management based on final pathology as the reference standard, biopsy had a negative predictive value of 0.69 and positive predictive value 1.0 for determining management. Of the 11 misclassified cases, 7 had a biopsy indicating grade 1 clear cell renal cancer which was upgraded to grade 2 (5) or grade 3 (2). After modifying the histological risk group assignment to account for undergrading of clear cell renal cancer, agreement improved to 97%, with a negative predictive value of 0.86 and a positive predictive value of 1.0. CONCLUSIONS: Our results suggest that compared to final pathology, biopsy of small renal masses accurately informs an algorithm incorporating size and histological risk group that directs the management of small renal masses.


Assuntos
Carcinoma de Células Renais/patologia , Neoplasias Renais/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha , Humanos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Medição de Risco , Adulto Jovem
10.
Transgenic Res ; 21(4): 785-95, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22038450

RESUMO

Both drought and high salinity stresses are major abiotic factors that limit the yield of agricultural crops. Transgenic techniques have been regarded as effective ways to improve crops in their tolerance to these abiotic stresses. Functional characterization of genes is the prerequisite to identify candidates for such improvement. Here, we have investigated the biological functions of an Oryza sativa Ribosome-inactivating protein gene 18 (OSRIP18) by ectopically expressing this gene under the control of CaMV 35S promoter in the rice genome. We have generated 11 independent transgenic rice plants and all of them showed significantly increased tolerance to drought and high salinity stresses. Global gene expression changes by Microarray analysis showed that more than 100 probe sets were detected with up-regulated expression abundance while signals from only three probe sets were down-regulated after over-expression of OSRIP18. Most of them were not regulated by drought or high salinity stresses. Our data suggested that the increased tolerance to these abiotic stresses in transgenic plants might be due to up-regulation of some stress-dependent/independent genes and OSRIP18 may be potentially useful in further improving plant tolerance to various abiotic stresses by over-expression.


Assuntos
Oryza , Plantas Geneticamente Modificadas , Proteínas Inativadoras de Ribossomos/genética , Estresse Fisiológico/genética , Secas , Regulação da Expressão Gênica de Plantas , Oryza/genética , Oryza/crescimento & desenvolvimento , Oryza/fisiologia , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/fisiologia , Proteínas Inativadoras de Ribossomos/fisiologia , Tolerância ao Sal/genética
11.
Plant Mol Biol ; 67(6): 603-14, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18493723

RESUMO

Ribosome-inactivating proteins (RIPs) are N-glycosidases that inhibit protein synthesis by depurinating rRNA. Despite their identification more than 25 years ago, little is known about their biological functions. Here, we report a genome-wide identification of the RIP family in rice based on the complete genome sequence analysis. Our data show that rice genome encodes at least 31 members of this family and they all belong to type 1 RIP genes. This family might have evolved in parallel to species evolution and genome-wide duplications represent the major mechanism for this family expansion. Subsequently, we analyzed their expression under biotic (bacteria and fungus infection), abiotic (cold, drought and salinity) and the phytohormone ABA treatment. These data showed that some members of this family were expressed in various tissues with differentiated expression abundances whereas several members showed no expression under normal growth conditions or various environmental stresses. On the other hand, the expression of many RIP members was regulated by various abiotic and biotic stresses. All these data suggested that specific members of the RIP family in rice might play important roles in biotic and abiotic stress-related biological processes and function as a regulator of various environmental cues and hormone signaling. They may be potentially useful in improving plant tolerance to various abiotic and biotic stresses by over-expressing or suppressing these genes.


Assuntos
Adaptação Fisiológica , Oryza/genética , Proteínas Inativadoras de Ribossomos Tipo 1/genética , Desidratação , Evolução Molecular , Duplicação Gênica , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Família Multigênica , Oryza/metabolismo , Oryza/microbiologia , Filogenia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Estrutura Terciária de Proteína , Proteínas Inativadoras de Ribossomos Tipo 1/classificação , Proteínas Inativadoras de Ribossomos Tipo 1/metabolismo , Cloreto de Sódio/farmacologia
12.
Diagn Cytopathol ; 35(9): 597-600, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17703444

RESUMO

We report a case of primary renal carcinoid arising in a horseshoe kidney. To the best of our knowledge this is the first case to be reported in the cytology literature, which has been diagnosed by fine needle aspiration (FNA). A 32-year-old male, presented to the Emory University Hospital, with a renal mass arising in a horseshoe kidney; along with a thyroid mass. FNA of the renal mass resulted in an initial diagnosis of renal cell carcinoma, unclassified. A thyroid aspiration was attempted later, and revealed a neuroendocrine morphology. This was compared with the renal aspiration and both of them were found to have similar morphology. With the help of immunostains, a diagnosis of renal carcinoid tumor metastatic to the thyroid was made. Thus, we demonstrate that renal carcinoid, being a rare entity, can pose a diagnostic challenge.


Assuntos
Carcinoma de Células Renais/secundário , Neoplasias Renais/patologia , Rim/anormalidades , Neoplasias da Glândula Tireoide/secundário , Adulto , Biópsia por Agulha Fina/métodos , Carcinoma de Células Renais/patologia , Humanos , Masculino , Metástase Neoplásica , Neoplasias da Glândula Tireoide/patologia
13.
Diagn Cytopathol ; 35(6): 342-7, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17497664

RESUMO

The distinction between malignant mesothelioma and adenocarcinoma is a diagnostic challenge in cytologic specimens of effusion fluids. As for today, no single antibody has demonstrated absolute sensitivity or specificity for Mesothelioma. D2-40 and podoplanin have recently been recognized to stain mesothelial cells. Our aim for this study was to evaluate the utility of these two markers as indicators of mesothelial cells using cell blocks by comparison with two other established mesothelial markers. A total of 40 cell blocks of effusion fluids including cases of epithelioid mesotheliomas, metastatic carcinomas and benign cases with reactive mesothelial cells were selected. A panel of immunostains including D2-40, podoplanin, CK5, and calretinin was performed. D2-40 and podoplanin were positive in 100% of mesothelioma cases in comparison to metastatic adenocarcinoma cases where the positivity was 0%. It is concluded that D2-40 and podoplanin are very useful markers for mesotheliomas. Since these markers are extremely helpful in differentiating epithelioid mesothelioma from metastatic adenocarcinoma, they shall be a valuable addition to the battery of markers used to differentiate the two entities.


Assuntos
Anticorpos Antineoplásicos , Mesotelioma/diagnóstico , Derrame Pleural Maligno/diagnóstico , Diagnóstico Diferencial , Humanos , Imuno-Histoquímica , Mesotelioma/patologia , Derrame Pleural Maligno/patologia
14.
Diagn Cytopathol ; 35(3): 164-6, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17415920

RESUMO

The authors present a case of cardiac angiosarcoma diagnosed by fine-needle aspiration (FNA) in a 33-year-old male. A percutaneous right atrial mass biopsy was performed via a right internal jugular venous approach and under echocardiographic guidance. FNA showed pleomorphic spindle-shaped cells present singly and in small clusters in a background of hemorrhage. Occasional pseudo-acini or microacinar structures were observed, that are lined with abnormal spindly to polygonal cells, indicative of vasoformative structures. Immunostain for CD31 was strongly positive. A diagnosis of cardiac angiosarcoma was made, following which, the patient underwent treatment with chemotherapy.


Assuntos
Ecocardiografia , Neoplasias Cardíacas/diagnóstico por imagem , Neoplasias Cardíacas/patologia , Hemangiossarcoma/diagnóstico por imagem , Hemangiossarcoma/patologia , Adulto , Biópsia por Agulha Fina , Humanos , Imageamento por Ressonância Magnética , Masculino
15.
Diagn Cytopathol ; 34(1): 41-4, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16355374

RESUMO

Salivary duct carcinoma (SDC) is a high-grade malignant tumor exhibiting aggressive growth with early regional and distant metastasis. We report a case of SDC in a 53-yr-old male with distant metastasis to an inguinal lymph node. The diagnosis of the primary tumor as well as the metastatic lesion was accomplished by fine-needle aspiration (FNA). Aggressive clinical management appears to be the main therapeutic option for long-term survival. Therefore, establishing an accurate preoperative diagnosis by FNA can have both clinical and prognostic relevance.


Assuntos
Biópsia por Agulha Fina , Carcinoma/diagnóstico , Metástase Linfática/diagnóstico , Ductos Salivares/patologia , Neoplasias das Glândulas Salivares/diagnóstico , Carcinoma/patologia , Humanos , Canal Inguinal , Masculino , Pessoa de Meia-Idade , Neoplasias das Glândulas Salivares/patologia
16.
Plant Cell Rep ; 24(10): 562-71, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16220342

RESUMO

A natural shift is taking place in the approaches being adopted by plant scientists in response to the accessibility of systems-based technology platforms. Metabolomics is one such field, which involves a comprehensive non-biased analysis of metabolites in a given cell at a specific time. This review briefly introduces the emerging field and a range of analytical techniques that are most useful in metabolomics when combined with computational approaches in data analyses. Using cases from Arabidopsis and other selected plant systems, this review highlights how information can be integrated from metabolomics and other functional genomics platforms to obtain a global picture of plant cellular responses. We discuss how metabolomics is enabling large-scale and parallel interrogation of cell states under different stages of development and defined environmental conditions to uncover novel interactions among various pathways. Finally, we discuss selected applications of metabolomics.


Assuntos
Perfilação da Expressão Gênica/tendências , Genômica/tendências , Metabolismo/genética , Biologia Molecular/tendências , Plantas/genética , Plantas/metabolismo , Bioquímica/métodos , Bioquímica/tendências , Bases de Dados Bibliográficas/tendências , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas/genética , Genoma de Planta/genética , Genômica/métodos , Biologia Molecular/métodos
17.
FEMS Microbiol Lett ; 243(2): 467-72, 2005 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-15686851

RESUMO

Twenty-four serovars of Bacillus thuringiensis (Bt) were screened by polymerase chain reaction to detect the presence of vegetative insecticidal protein gene (vip)-like sequences by using vip3Aa1-specific primers. vip-like gene sequences were identified in eight serovars. These genes were cloned and sequenced. The deduced amino acid sequence of the vip3Aa14 gene from Bacillus thuringiensis tolworthi showed considerable differences as compared to those of Vips reported so far. The vip3Aa14 gene from Bt tolwarthi was expressed in Escherichia coli using expression vector pET29a. The expressed Vip3Aa14 protein was found in cytosolic supernatant as well as pellet fraction, but the protein was more abundant in the cytosolic supernatant fraction. Both full-length and truncated (devoid of signal sequence) Vips were highly toxic to the larvae of Spodoptera litura and Plutella xylostella. Truncation of Vip3Aa14 protein at N-terminus did not affect its insecticidal activity.


Assuntos
Bacillus thuringiensis/crescimento & desenvolvimento , Proteínas de Bactérias , Toxinas Bacterianas , Endotoxinas , Animais , Bacillus thuringiensis/classificação , Bacillus thuringiensis/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/toxicidade , Toxinas Bacterianas/genética , Toxinas Bacterianas/isolamento & purificação , Toxinas Bacterianas/metabolismo , Toxinas Bacterianas/toxicidade , Bioensaio , Endotoxinas/genética , Endotoxinas/isolamento & purificação , Endotoxinas/metabolismo , Endotoxinas/toxicidade , Larva/crescimento & desenvolvimento , Dados de Sequência Molecular , Mariposas/crescimento & desenvolvimento , Controle Biológico de Vetores , Folhas de Planta/química , Análise de Sequência de DNA , Spodoptera/crescimento & desenvolvimento
19.
J Biosci ; 28(5): 637-46, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-14517367

RESUMO

Terpenoids are known to have many important biological and physiological functions. Some of them are also known for their pharmaceutical significance. In the late nineties after the discovery of a novel non-mevalonate (non-MVA) pathway, the whole concept of terpenoid biosynthesis has changed. In higher plants, the conventional acetate-mevalonate (Ac-MVA) pathway operates mainly in the cytoplasm and mitochondria and synthesizes sterols, sesquiterpenes and ubiquinones predominantly. The plastidic non-MVA pathway however synthesizes hemi-, mono-, sesqui- and di-terpenes, along with carotenoids and phytol chain of chlorophyll. In this paper, recent developments on terpenoids biosynthesis are reviewed with respect to the non-MVA pathway.


Assuntos
Ácido Mevalônico/metabolismo , Plantas/metabolismo , Terpenos/metabolismo , Acetatos/metabolismo , Eritritol/química , Eritritol/metabolismo , Plantas/genética , Terpenos/química
20.
J Biosci ; 28(4): 479-87, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12799494

RESUMO

Palmarosa inflorescence with partially opened spikelets is biogenetically active to incorporate [U-14C]sucrose into essential oil. The percent distribution of 14C-radioactivity incorporated into geranyl acetate was relatively higher as compared to that in geraniol, the major essential oil constituent of palmarosa. At the partially opened spikelet stage, more of the geraniol synthesized was acetylated to form geranyl acetate, suggesting that majority of the newly synthesized geraniol undergoes acetylation, thus producing more geranyl acetate. In vitro development of palmarosa inflorescence, fed with [U-14C]sucrose, resulted in a substantial reduction in percent label from geranyl acetate with a corresponding increase in free geraniol, thereby suggesting the role of an esterase in the production of geraniol from geranyl acetate. At time course measurement of 14CO2 incorporation into geraniol and geranyl acetate substantiated this observation. Soluble acid invertase was the major enzyme involved in the sucrose breakdown throughout the inflorescence development. The activities of cell wall bound acid invertase, alkaline invertase and sucrose synthase were relatively lower as compared to the soluble acid invertase. Sucrose to reducing sugars ratio decreased till fully opened spikelets stage, concomitant with increased acid invertase activity and higher metabolic activity. The phenomenon of essential oil biosynthesis has been discussed in relation to changes in these physiological parameters.


Assuntos
Cymbopogon/metabolismo , Sacarose/metabolismo , Terpenos/metabolismo , Monoterpenos Acíclicos , Fenômenos Bioquímicos , Bioquímica , Metabolismo dos Carboidratos , Esterases/metabolismo , Hidrólise , Fenômenos Fisiológicos Vegetais , Fatores de Tempo
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