RESUMEN
Squalene synthase (SQS: EC 2.5.1.21) is a potential branch point regulatory enzyme and represents the first committed step to diverge the carbon flux from the main isoprenoid pathway towards sterol biosynthesis. In the present study, cloning and characterization of Withania somnifera squalene synthase (WsSQS) cDNA was investigated subsequently followed by its heterologous expression and preliminary enzyme activity. Two different types of WsSQS cDNA clones (WsSQS1and WsSQS2) were identified that contained an open reading frames of 1,236 and 1,242 bp encoding polypeptides of 412 and 414 amino acids respectively. Both WsSQS isoforms share 99 % similarity and identity with each other. WsSQS deduced amino acids sequences, when compared with SQS of other plant species, showed maximum similarity and identity with Capsicum annuum followed by Solanum tuberosum and Nicotiana tabacum. To obtain soluble recombinant enzymes, 24 hydrophobic amino acids were deleted from the carboxy terminus and expressed as 6X His-Tag fusion protein in Escherichia coli. Approximately 43 kDa recombinant protein was purified using Ni-NTA affinity chromatography and checked on SDS-PAGE. Preliminary activity of the purified enzymes was determined and the products were analyzed by gas chromatograph-mass spectrometer (GC-MS). Quantitative real-time PCR (qRT-PCR) analysis showed that WsSQS expresses more in young leaves than mature leaves, stem and root.
Asunto(s)
Farnesil Difosfato Farnesil Transferasa/genética , Farnesil Difosfato Farnesil Transferasa/metabolismo , Regulación de la Expresión Génica de las Plantas , Withania/genética , Withania/metabolismo , Secuencia de Aminoácidos , Clonación Molecular , ADN Complementario , Escherichia coli/genética , Escherichia coli/metabolismo , Farnesil Difosfato Farnesil Transferasa/aislamiento & purificación , Datos de Secuencia Molecular , Filogenia , Proteínas Recombinantes/genética , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Alineación de Secuencia , Withania/clasificaciónRESUMEN
In the western mountainous region of Khyber Pakhtunkhwa Pakistan at the Shangla district, we found Physalis ixocarpa for the first time, not yet reported from Pakistan. Physalis ixocarpa was unidentified and has no ethnobotanical record in the flora of Pakistan. It is a member of family Solanaceae and having a close relation with Solanum tuberosum and Lycopersicon esculentum. The stem is prostrate with a dichotomous pattern of branches having leaves flower and fruits. Leaves are smooth, ovate and the margins of leaf blade dentation are poorly developed. The average length and width of the leaves are 6.50 and 3.61 cm respectively. P. ixocarpa grows to the length of 4-5 feet and an annual herb. The flowers of the plants are yellow in color and having purple color spots on the petals which are star-shaped. The round berry fruits are surrounded by persistent calyx and purple in color. The fruits are the 3-6cm in diameter. The plants are found in the different localities of district Shangla especially in Bar and Koz Kana. The life cycle of reporting plant is started in May and completed in November.
Asunto(s)
Physalis , Etnobotánica , Pakistán , Hojas de la Planta , PlantasRESUMEN
This study aimed to identify the phylogenetic similarities among the muntjac (Muntiacus spp.). The phylogenetic similarities among seven major muntjac species were studied by comparing the nucleotide sequence of 16s rRNA and cytochrome b genome. Nucleotide sequences, retrieved from NCBI databases were aligned by using DNASTAR software. A phylogenetic tree was created for the selected species of muntjac by using the maximum likelihood method on MEGA7 software. The results of nucleotide sequences (16s rRNA) showed phylogenetic similarities between, the M. truongsonensis and M. rooseveltorum had the highest (99.2%) while the lowest similarities (96.8%) found between M. crinifrons and M. putaoensi. While the results of nucleotide sequences (Cty b) showed the highest similarity (100%) between M. muntjak and M. truongsonensis and the lowest s (91.5%) among M. putaoensis and M. crinifrons. The phylogenetic tree of muntjac species (16s rRNA gene) shows the main two clusters, the one including M. putaoensis, M. truongsonensis, M. rooseveltorum, and M. muntjak, and the second one including M. crinifrons and M. vuquangensis. The M. reevesi exists separately in the phylogenetic tree. The phylogenetic tree of muntjac species using cytochrome b genes shows that the M. muntjak and M. truongsonensis are clustered in the same group.
Asunto(s)
Citocromos b , Ciervo Muntjac , Animales , Secuencia de Bases , Citocromos b/genética , Ciervo Muntjac/genética , Filogenia , ARN Ribosómico 16S/genéticaRESUMEN
This study aimed to identify the phylogenetic similarities among the muntjac (Muntiacus spp.). The phylogenetic similarities among seven major muntjac species were studied by comparing the nucleotide sequence of 16s rRNA and cytochrome b genome. Nucleotide sequences, retrieved from NCBI databases were aligned by using DNASTAR software. A phylogenetic tree was created for the selected species of muntjac by using the maximum likelihood method on MEGA7 software. The results of nucleotide sequences (16s rRNA) showed phylogenetic similarities between, the M. truongsonensis and M. rooseveltorum had the highest (99.2%) while the lowest similarities (96.8%) found between M. crinifrons and M. putaoensi. While the results of nucleotide sequences (Cty b) showed the highest similarity (100%) between M. muntjak and M. truongsonensis and the lowest s (91.5%) among M. putaoensis and M. crinifrons. The phylogenetic tree of muntjac species (16s rRNA gene) shows the main two clusters, the one including M. putaoensis, M. truongsonensis, M. rooseveltorum, and M. muntjak, and the second one including M. crinifrons and M. vuquangensis. The M. reevesi exists separately in the phylogenetic tree. The phylogenetic tree of muntjac species using cytochrome b genes shows that the M. muntjak and M. truongsonensis are clustered in the same group.
Este estudo visou identificar as semelhanças filogenéticas entre os muntjac (Muntiacus spp.). As semelhanças filogenéticas entre sete grandes espécies muntjac foram estudadas comparando a sequência de nucleótidos de 16s rRNA e genoma citocromo b. As sequências de nucleótidos, obtidas a partir de bases de dados NCBI, foram alinhadas utilizando o software DNASTAR. Foi criada uma árvore filogenética para as espécies selecionadas de muntjac utilizando o método de probabilidade máxima no software MEGA7. Os resultados das sequências de nucleótidos (16s rRNA) mostraram semelhanças filogenéticas entre o M. truongsonensis e o M. rooseveltorum tiveram o maior número (99,2%) enquanto as semelhanças mais baixas (96,8%) encontradas entre M. crinifrons e M. putaoensi. Enquanto os resultados das sequências de nucleótidos (Cty-b) apresentaram a maior semelhança (100%) entre M. muntjak e M. truongsonensis e os mais baixos (91,5%) entre M. putaoensis e M. crinifrons. A árvore filogenética das espécies muntjac (gene rRNA 16s) mostra os dois principais aglomerados, o que inclui M. putaoensis, M. truongsonensis, M. rooseveltorum e M. muntjak, e o segundo incluindo M. crinifrons e M. vuquangensis. O M. reevesi existe separadamente na árvore filogenética. A árvore filogenética das espécies muntjac usando genes citocromo b mostra que os M. muntjak e M. truongsonensis estão agrupados no mesmo grupo.
Asunto(s)
Animales , Ciervo Muntjac/clasificación , Ciervo Muntjac/genética , Citocromos b/análisis , /análisisRESUMEN
Abstract This study aimed to identify the phylogenetic similarities among the muntjac (Muntiacus spp.). The phylogenetic similarities among seven major muntjac species were studied by comparing the nucleotide sequence of 16s rRNA and cytochrome b genome. Nucleotide sequences, retrieved from NCBI databases were aligned by using DNASTAR software. A phylogenetic tree was created for the selected species of muntjac by using the maximum likelihood method on MEGA7 software. The results of nucleotide sequences (16s rRNA) showed phylogenetic similarities between, the M. truongsonensis and M. rooseveltorum had the highest (99.2%) while the lowest similarities (96.8%) found between M. crinifrons and M. putaoensi. While the results of nucleotide sequences (Cty b) showed the highest similarity (100%) between M. muntjak and M. truongsonensis and the lowest s (91.5%) among M. putaoensis and M. crinifrons. The phylogenetic tree of muntjac species (16s rRNA gene) shows the main two clusters, the one including M. putaoensis, M. truongsonensis, M. rooseveltorum, and M. muntjak, and the second one including M. crinifrons and M. vuquangensis. The M. reevesi exists separately in the phylogenetic tree. The phylogenetic tree of muntjac species using cytochrome b genes shows that the M. muntjak and M. truongsonensis are clustered in the same group.
Resumo Este estudo visou identificar as semelhanças filogenéticas entre os muntjac (Muntiacus spp.). As semelhanças filogenéticas entre sete grandes espécies muntjac foram estudadas comparando a sequência de nucleótidos de 16s rRNA e genoma citocromo b. As sequências de nucleótidos, obtidas a partir de bases de dados NCBI, foram alinhadas utilizando o software DNASTAR. Foi criada uma árvore filogenética para as espécies selecionadas de muntjac utilizando o método de probabilidade máxima no software MEGA7. Os resultados das sequências de nucleótidos (16s rRNA) mostraram semelhanças filogenéticas entre o M. truongsonensis e o M. rooseveltorum tiveram o maior número (99,2%) enquanto as semelhanças mais baixas (96,8%) encontradas entre M. crinifrons e M. putaoensi. Enquanto os resultados das sequências de nucleótidos (Cty-b) apresentaram a maior semelhança (100%) entre M. muntjak e M. truongsonensis e os mais baixos (91,5%) entre M. putaoensis e M. crinifrons. A árvore filogenética das espécies muntjac (gene rRNA 16s) mostra os dois principais aglomerados, o que inclui M. putaoensis, M. truongsonensis, M. rooseveltorum e M. muntjak, e o segundo incluindo M. crinifrons e M. vuquangensis. O M. reevesi existe separadamente na árvore filogenética. A árvore filogenética das espécies muntjac usando genes citocromo b mostra que os M. muntjak e M. truongsonensis estão agrupados no mesmo grupo.
RESUMEN
Taxol is perhaps the most successful drug used for the treatment of various cancers. Comprehensive literature accumulated on therapeutics of the drug has indicated numerous side effects. In this paper, by use of fluorescence spectroscopy, it is shown that taxol binds to DNA with an affinity constant (Ka) of 1.08 x 10(7) M-1. This binding is accompanied by a large 'red edge excitation shift' (REES) of fluorescence emission maximum in taxol-DNA complex. The results point to an interaction of taxol with its core eight-membered ring in the DNA groove and the three phenyl rings projecting away from the DNA. The drug encompasses about two base pairs of DNA upon binding to it. Systematic studies with taxol analogues confirms such a mode of binding. These interesting findings on hitherto unknown taxol-DNA interactions may have clinical implications in view of its large number of side effects and pharmacokinetics.
Asunto(s)
Antineoplásicos Fitogénicos/metabolismo , ADN/metabolismo , Paclitaxel/metabolismo , Dicroismo Circular , ADN/biosíntesis , ADN/química , Espectrometría de FluorescenciaRESUMEN
The developmental patterns of the nitrogen assimilating enzymes were investigated and compared in the non-shoot forming and the shoot forming callus cultures of sugarane. In the shoot forming tissue the pre-emergence period od shoots was characterised by increasing activities of glutamine synthetase and glutamate synthase. The activity of these enzymes during the corresponding period in the non-shoot forming callus was found to decline. Although the activity of glutamate dehydrogenase in the shoot forming callus during the period of pre-emergence of shoots did not show any appreciable change, in the non-shoot forming callus, it increased during the corresponding period. The developmental patterns of nitrate reductase in both the programmes were identical except for the fact that in the shoot forming tissue the nitrate reductase activity was higher at all times than in the non-shoot forming callus. The data suggest that (a) shoot differentiation occurs concomitant with peak glutamine synthetase, glutamate synthase, and nitrate reductase activity, whereas the glutamate dehydrogenase activity is at its lowest, (b) better mobilization of nitrate occurs in the shoot forming callus and (c) the glutamine synthetase/glutamate synthase pathway becomes operative prior to shoot differentiation.
RESUMEN
This study was carried out as a prerequisite to evaluate the therapeutic potential of Camellia varieties. The crude extracts of six different plants of green tea Camellia assamica and Camellia sinensis were tested against three Gram-positive and four Gram-negative bacteria using agar disk diffusion method at 50 mg/ml concentration. 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) and diphenyl-(2,4,6-trinitrophenyl)iminoazanium free radical scavenging methods were performed to evaluate the antioxidant potential. Phytochemical constituents and trace metals were detected through thin layer chromatography and Inductively Coupled Plasma Atomic Emission Spectrophotometer, respectively. The maximum inhibition of Staphylococcus aureus was recorded by dimethyl sulphoxide extracts of green tea varieties. The measured zone of inhibition of dimethyl sulphoxide extracts by Qimen was (10.00±0.0 mm), Japanese (10.00±0.0 mm), Turkish (10.00±0.0 mm), Indonesian (8.33±1.0 mm), P3 clone (10.00±0.0 mm) and Sri Lankan (10.00±0.0 mm). Maximum scavenging potential activity was found with ethanol, methanol and dimethyl sulphoxide extracts. Spot screening of TLC-developed plates indicated that the presence of active biological compounds such as flavonoids, proteins, phenols, alkaloids and glycosides also exhibited strong activity against tested bacterial strains. This study reveals the potential biological activities of Camellia assamica and Camellia sinensis having massive phytochemical constituents and trace elements.
RESUMEN
The endophytic fungal populations of different tissues of Taxus baccata grown at high altitudes in West Bengal, India were explored. These isolated fungal populations represented different genera, which were screened for taxol production using immunoassay technique. The culture AAT-TS-4(1) that produced taxol was identified as Gliocladium sp. based on its cultural, morphological characteristics, internal transcribed spacer, and 18S rRNA sequence analysis. Kinetics of taxol production as a function of culture growth were investigated.
RESUMEN
The in vivo nitrate reductase activity in 8 day old dark-grown sugarcane callus was over three fold that of the light-grown callus. NADH (0.3 mM) in the reaction system, increased the in vivo nitrate reductase activity by more than two fold both in the dark- and the light-grown callus tissues. The NADH dependence of nitrate reductase activity followed Michaelian kinetics. The apparent Km values for NADH were 0.083 mM and 0.20 mM, respectively, for the dark- and the light-grown callus. In vivo nitrate reductase activity in green sugarcane leaves (field grown) was unaffected by NADH in the reaction system. Under the standard conditions of assay up to 60% of the NADH penetrated into the sugarcane callus within 2 min. No penetration of NADH into the sugarcane leaf discs was, however, recorded under identical conditions.
RESUMEN
Interactions of Vibrio (formerly Achromobacter) fischeri nitrite reductase were studied by electron paramagnetic resonance spectroscopy. The spectrum of the oxidized enzyme showed a number of features which were attributed to two low-spin ferric hemes. These comprised an unusual derivative peak at g = 3.7 and a spectrum at g = 2.88, 2.26, and 1.51. Neither heme was reactive in the oxidized state with the substrate nitrite and with cyanide and azide. When frozen under turnover conditions (i.e., reduction in the presence of excess nitrite), the enzyme showed the spectrum of a nitrosyl heme derivative. The g = 2.88, 2.26, and 1.51 signals reappeared partially on reoxidation by nitrite, indicating that the nitrosyl species which remained arose from the g = 3.7 heme. The nitrosyl derivative showed a 14N nuclear hyperfine splitting, Az = 1.65 mT. The nitrosyl derivative was produced by treatment of the oxidized nitrite reductase with nitric oxide or hydroxylamine. Exchange of nitric oxide between the nitrosyl derivative and NO gas in solution was observed by using the [15N]nitrosyl compound. A possible reaction cycle for the enzyme is discussed, which involves reduction of the enzyme followed by binding of nitrite to one heme and formation of the nitrosyl intermediate.
Asunto(s)
Hemo/análisis , NADH NADPH Oxidorreductasas/metabolismo , Nitrito Reductasas/metabolismo , Vibrio/enzimología , Espectroscopía de Resonancia por Spin del Electrón/métodos , Cinética , Nitrito Reductasas/aislamiento & purificación , Oxidación-ReducciónRESUMEN
Cell-specific and light-regulated expression of the beta-glucuronidase (GUS) reporter gene from maize cab-m1 and rbcS-m3 promoter sequences was studied in maize leaf segments by using an in situ transient expression microprojectile bombardment assay. The cab-m1 gene is known to be strongly photoregulated and to be expressed almost exclusively in mesophyll cells (MC) but not in bundle sheath cells (BSC). Expression of GUS from a 1026-base-pair 5' promoter fragment of cab-m1 is very low in dark-grown leaves; GUS expression is increased about 10-fold upon illumination of dark-grown leaves. In illuminated leaves, the ratio of GUS expression in MC vs. BSC is about 10:1. The cab-m1 region between 868 and 1026 base pairs 5' to the translation start confers strong MC-preferred expression on the remainder of the chimeric gene in illuminated leaves, but a region between -39 and -359 from the translation start is required for photoregulated expression. Transcripts of rbcS-m3 are found in BSC but not in MC and are about double in BSC of greening dark-grown seedlings. In contrast to the behavior of the cab-m1-GUS construct, GUS expression driven by 2.1 kilobase pairs of the rbcS-m3 5' region was about twice as high in MC as in BSC of unilluminated dark-grown maize leaves. The number of BSC, but not MC, expressing GUS nearly doubled upon greening of bombarded etiolated leaves. These data suggest that the 5' region of rbcS-m3 used here could be responsible for most of the light-dependent increase in rbcS-m3 transcripts observed in BSC of greening leaves and that transcriptional or posttranscriptional mechanisms are responsible for the lack of rbcS-m3 transcripts in MC.