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951.
During the early Eocene (~55–52 Ma), when the Indian subcontinent relished equatorial climatic conditions, lignite was deposited along its north western margin. Lignite mines of northwestern India have proved to be an outstanding resource for palaeoenvironmental information. The Vastan lignite mine of the early Eocene age situated near Surat district (Gujarat) is one of the well-dated and fossiliferous lignite mines in western India. A fossil wood, retrieved from this mine, is systematically described and shows a strong resemblance to the modern genus Chisocheton of the family Meliaceae. Plant fossils are the best source to reconstruct the palaeoenvironment of any region, and here a luxurious, highly diverse tropical evergreen forest is interpreted in and around the fossil locality in contrast to the tropical thorn forest of the present day. This early Eocene highly diverse equatorial forest, once covered a significant portion of the Indian subcontinent, is now restricted in fringes known as Western Ghats in south India attesting to changes in climate. 相似文献
952.
953.
Devara Divya Tarun Kumar Bhattacharya Manthani Gnana Prakash R. N. Chatterjee Renu Shukla Pothana Boyina Guru Vishnu Amirthalingam Vinoth Kotha Dushyanth 《Molecular biology reports》2018,45(4):477-495
A study was carried out to characterize and explore the expression profile of BMP 3 gene in control broiler and control layer chicken. The total open reading frame of BMP 3 (1389 bp) was cloned and sequenced. The control broiler and control layer chicken showed variation at nucleotide and amino acid level with reference gene (Gallus gallus, NCBI Acc. No. NM_001034819). When compared to reference gene, the control broiler showed four nucleotide differences (c.192A>G, c.519C>T, 903G>A and 960C>G), while, control layer showed variation at c.33G>C, 192A>G, 858G>A, 904G>A, 960C>G and 1257C>T making six differences in total. However, between control broiler and control layer lines, nucleotide differences was observed at c.33G>C, 519T>C, 858G>A, 903A>G, 904G>A and 1257C>T. The change at amino acid level between reference and control broiler was p.D320N and with control layer chicken, it was p.D302N and p.D320N. On the other hand, a single amino acid difference (p.D302N) was observed between the control broiler and control layer chicken lines. The phylogenetic study displayed a close relationship between broiler and layer lines and reference gene and also with other avian species resulting in a cluster formation. These cluster in turn displayed a distant link with the mammalian species. The expression profile of BMP 3 gene exhibited a variation at different stages of embryonic development and also at post embryonic period among the lines with control layer showing higher expression than that of broiler chicken. The protein was also detected in bone marrow tissue of broiler and layer lines by western blotting. It is concluded that the BMP 3 gene sequence differed at nucleotide and amino acid level among the lines and the gene expressed differentially at different periods of embryonic development and also at post hatch period. 相似文献
954.
Xylanases are one of the important hydrolytic enzymes which hydrolyze the β-1, 4 xylosidic linkage of the backbone of the xylan polymeric chain which consists of xylose subunits. Xylanases are mainly found in plant cell walls and are produced by several kinds of microorganisms such as fungi, bacteria, yeast, and some protozoans. The fungi are considered as most potent xylanase producers than that of yeast and bacteria. There is a broad series of industrial applications for the thermostable xylanase as an industrial enzyme. Thermostable xylanases have been used in a number of industries such as paper and pulp industry, biofuel industry, food and feed industry, textile industry, etc. The present review explores xylanase–substrate interactions using gene-editing tools toward the comprehension in improvement in industrial stability of xylanases. The various protein-engineering and metabolic-engineering methods have also been explored to improve operational stability of xylanase. Thermostable xylanases have also been used for improvement in animal feed nutritional value. Furthermore, they have been used directly in bakery and breweries, including a major use in paper and pulp industry as a biobleaching agent. This present review envisages some of such applications of thermostable xylanases for their bioengineering. 相似文献
955.
Arun Kumar Dangi Babita Sharma Ishu Khangwal Pratyoosh Shukla 《Molecular biotechnology》2018,60(8):636-650
Plants are continually facing biotic and abiotic stresses, and hence, they need to respond and adapt to survive. Plant response during multiple and combined biotic and abiotic stresses is highly complex and varied than the individual stress. These stresses resulted alteration of plant behavior through regulating the levels of microRNA, heat shock proteins, epigenetic variations. These variations can cause many adverse effects on the growth and development of the plant. Further, in natural conditions, several abiotic stresses causing factors make the plant more susceptible to pathogens infections and vice-versa. A very intricate and multifaceted interactions of various biomolecules are involved in metabolic pathways that can direct towards a cross-tolerance and improvement of plant’s defence system. Systems biology approach plays a significant role in the investigation of these molecular interactions. The valuable information obtained by systems biology will help to develop stress-resistant plant varieties against multiple stresses. Thus, this review aims to decipher various multilevel interactions at the molecular level under combinatorial biotic and abiotic stresses and the role of systems biology to understand these molecular interactions. 相似文献
956.
957.
Molineria jashpurica A.P. Tiwari, Mujaffar & A.N. Shukla (Hypoxidaceae), a new species from the Jashpur district of Chhattisgrah, India is described and illustrated. It is closely similar to M. gracilis and M. trichocarpa, but differs by shorter pseudopetiole, broad and glabrous leaf blade, delicate scape, fewer flowers and clavate stigma. A key for identification of all Molineria species is also provided. The conservation status of the new species is assessed as ‘Critically Endangered’ (CR) according to IUCN red list category and criteria. 相似文献
958.
Mahendra Kumar Shukla Manuel J. Llansola-Portoles Martin Tichý Andrew A. Pascal Bruno Robert Roman Sobotka 《Photosynthesis research》2018,137(1):29-39
Cyanobacteria possess a family of one-helix high-light-inducible proteins (HLIPs) that are widely viewed as ancestors of the light-harvesting antenna of plants and algae. HLIPs are essential for viability under various stress conditions, although their exact role is not fully understood. The unicellular cyanobacterium Synechocystis sp. PCC 6803 contains four HLIPs named HliA–D, and HliD has recently been isolated in a small protein complex and shown to bind chlorophyll and β-carotene. However, no HLIP has been isolated and characterized in a pure form up to now. We have developed a protocol to purify large quantities of His-tagged HliC from an engineered Synechocystis strain. Purified His-HliC is a pigmented homo-oligomer and is associated with chlorophyll and β-carotene with a 2:1 ratio. This differs from the 3:1 ratio reported for HliD. Comparison of these two HLIPs by resonance Raman spectroscopy revealed a similar conformation for their bound β-carotenes, but clear differences in their chlorophylls. We present and discuss a structural model of HliC, in which a dimeric protein binds four chlorophyll molecules and two β-carotenes. 相似文献
959.
Jeffrey L. Ram Umesh A. Shukla Rajesh Parti Roy L. Goines 《Developmental neurobiology》1984,15(3):197-206
Serotonin [5-hydroxytryptamine (5-HT)] enhances acetyl choline (ACh)-elicited contractures of Aplysia buccal muscles E1 and I5. The possible role of external calcium in regulating the magnitude of ACh contracture in the presence and absence of 5-HT was investigated. Superfusion of E1 with zero calcium medium caused ACh contractures to fail within one to two minutes. Recovery of ACh contracture upon restoring normal medium occurred within two to four minutes. In the absence of 5-HT, ACh contracture decreased proportionally to external [Ca++] in the concentration range of 0–10 mM; however, the amount of enhancement of of ACh contracture following 5-HT treatment did not decrease with external [Ca++] as long as [Ca++] was above a threshold concentration that varied from preparation to preparation. For most preparations, the enhancement of ACh contracture by 5-HT was dependent on the presence of external calcium during 5-HT treatment. Calcium influx into muscles E1 and I5 increased approximately two and a half fold in the presence of 10?6 M 5-HT. A model in which 5-HT brings about calcium “loading” of an ACh releasable intracellular storage site is discussed. 相似文献
960.
V K Tandon N Pandey B R Shukla 《Anthropologischer Anzeiger; Bericht über die biologisch-anthropologische Literatur》1979,37(1):42-49
On n = 320 nonrelated Kureel Chamars (160 males, 160 females) from Lucknow and neighbouring villages and n = 314 nonrelated Jaiswar Chamars (160 males, 154 females) from Jaunpur the frequency of colourvision deficiency was examined. In the Kureel Chamars the frequency of deuteranopia comes to a total of 1.25% (males: 25%, females: 0.0%), in the Jaiswar Chamars to a total of 1.91% (males: 3.13%, females: 0.65%). Protanopes were only found in the Kureel Chamars (0.63%; males: 1.25%, females: 0.0%). These observations are discussed and compared with those obtained on other Indian populations. 相似文献