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1.
Changes in the protein and steroid hormones of follicular fluid, aspirated from different follicles of sheep and human ovaries, have been measured and correlated with the size of the follicles. As the fluid contains a number of proteins, steroids have been measured directly and after ether extraction. The follicular fluid concentrations of progesterone and 17 beta-oestradiol measured directly in the fluid increased with the size of the follicles. The levels of free testosterone remained constant in all sizes of follicles, while those of bound hormone showed a 10- to 15-fold increase over the free testosterone concentrations in both the sheep and human follicular fluid. A decrease in the levels of bound testosterone in the fluid of large follicles (LFFL) coincided with the increase in bound 17 beta-oestradiol, suggesting the possible conversion of bound testosterone to oestrogen as the follicle attained maturity. The ratio of follicle-stimulating hormone (FSH) to luteinizing hormone (LH) varied in the fluid obtained from different size follicles, being 1:7 in small (SFFL), 1.3.5 in medium (MFFL) and 1:2.3 in large (LFFL) follicles of sheep ovaries. The LH content of follicular fluid of different size follicles appeared to be the same, with LFFL showing a minor increase over SFFL. In the human, the fluid from medium follicles contained very little LH compared to LFFL. These differences in the pattern of LH levels present in the fluid from different size follicles between human and sheep ovaries presumably reflect species variations in the entry of LH into the follicles. 相似文献
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The Natural Occurrence of Chickpea Chlorotic Dwarf Geminivirus in Chickpea and Faba Bean in the Sudan 总被引:1,自引:0,他引:1
A survey of faba bean and chickpea for virus infection, conducted during February 1994 in the Sudan, showed that bean yellow mosaic potyvirus and broad bean mottle bromovirus occurred commonly in both crops. Chickpea chlorotic dwarf geminivirus (CCDV) was detected for the first time in naturally infected chickpeas and faba beans. This is the first report of natural CCDV infection of chickpeas outside India and the first record of chickpea and faba bean infection in West Asia and North Africa (WANA). 相似文献
4.
Efficient synthesis of large numbers of viable sphaeroplast from Saccharomyces cerevisiae has been found to be influenced by a number of factors. In this case, Trichoderma harzianum, NCIM 1185, culture filtrate has been used to prepare sphaeroplast from Saccharomyces cerevisiae, NCIM 3288. A method has been devised to isolate large number of viable sphaeroplast from the cell. Detailed analysis of various factors affecting the formation of sphaeroplasts from Saccharomyces cerevisiae has not yet been reported. This study showed critical analysis of various factors which influenced sphaeroplast formation. Most suitable conditions were: Age of the organism in slant — 1 d, cell age in liquid medium — 24 h, time of incubation of cell with 0.3% -mercaptoethanol — 30 min, level of lytic ezyme concentration — 79.2 ml, concentration of cell (dry wt. equivalent) — 0.1262 g, time of contact with lytic enzyme — 25 min, temperature of sphaeroplast formation — 30 °C, phosphate buffer — 25 mM of pH 6.5 and KCl as osmotic stabilizer — 0.7 M. 相似文献
5.
Alice B.M. Lanne Alice Goode Charlotte Prattley Divya Kumari Mette Ryun Drasbek Paul Williams Raquel Conde-Álvarez Ignacio Moriyón Boyan B. Bonev 《生物化学与生物物理学报:生物膜》2019,1861(1):83-92
Nisin is a lanthionine antimicrobial effective against diverse Gram-positive bacteria and is used as a food preservative worldwide. Its action is mediated by pyrophosphate recognition of the bacterial cell wall receptors lipid II and undecaprenyl pyrophosphate. Nisin/receptor complexes disrupt cytoplasmic membranes, inhibit cell wall synthesis and dysregulate bacterial cell division. Gram-negative bacteria are much more tolerant to antimicrobials including nisin. In contrast to Gram-positives, Gram-negative bacteria possess an outer membrane, the major constituent of which is lipopolysaccharide (LPS). This contains surface exposed phosphate and pyrophosphate groups and hence can be targeted by nisin. Here we describe the impact of LPS on membrane stability in response to nisin and the molecular interactions occurring between nisin and membrane-embedded LPS from different Gram-negative bacteria. Dye release from liposomes shows enhanced susceptibility to nisin in the presence of LPS, particularly rough LPS chemotypes that lack an O-antigen whereas LPS from microorganisms sharing similar ecological niches with antimicrobial producers provides only modest enhancement. Increased susceptibility was observed with LPS from pathogenic Klebsiella pneumoniae compared to LPS from enteropathogenic Salmonella enterica and gut commensal Escherichia coli. LPS from Brucella melitensis, an intra-cellular pathogen which is adapted to invade professional and non-professional phagocytes, appears to be refractory to nisin. Molecular complex formation between nisin and LPS was studied by solid state MAS NMR and revealed complex formation between nisin and LPS from most organisms investigated except B. melitensis. LPS/nisin complex formation was confirmed in outer membrane extracts from E. coli. 相似文献
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Gagan D. Gupta Swetha M. G. Sudha Kumari Ramya Lakshminarayan Gautam Dey Satyajit Mayor 《PloS one》2009,4(8)
In mammalian cells, endocytosis of the fluid phase and glycosylphosphatidylinositol-anchored proteins (GPI-APs) forms GEECs (GPI-AP enriched early endosomal compartments) via an Arf1- and Cdc42-mediated, dynamin independent mechanism. Here we use four different fluorescently labeled probes and several markers in combination with quantitative kinetic assays, RNA interference and high resolution imaging to delineate major endocytic routes in Drosophila cultured cells. We find that the hallmarks of the pinocytic GEEC pathway are conserved in Drosophila and identify garz, the fly ortholog of the GTP exchange factor GBF1, as a novel component of this pathway. Live confocal and TIRF imaging reveals that a fraction of GBF1 GFP dynamically associates with ABD RFP (a sensor for activated Arf1 present on nascent pinosomes). Correspondingly, a GTP exchange mutant of GBF1 has altered ABD RFP localization in the evanescent field and is impaired in fluid phase uptake. Furthermore, GBF1 activation is required for the GEEC pathway even in the presence of Brefeldin A, implying that, like Arf1, it has a role in endocytosis that is separable from its role in secretion. 相似文献
8.
Verma M Kaur J Kumar M Kumari K Saxena A Anand S Nigam A Ravi V Raghuvanshi S Khurana P Tyagi AK Khurana JP Lal R 《Journal of bacteriology》2011,193(19):5562-5563
Amycolatopsis mediterranei S699 is an actinomycete that produces an important antibiotic, rifamycin B. Semisynthetic derivatives of rifamycin B are used for the treatment of tuberculosis, leprosy, and AIDS-related mycobacterial infections. Here, we report the complete genome sequence (10.2 Mb) of A. mediterranei S699, with 9,575 predicted coding sequences. 相似文献
9.
Twelve fungi namelyAlternaria alternata, Aspergillus flavus, A niger, A ochraceus, Actinomucor repens, Capnodoium spp., Curvularia lunata, Fusarium
pallidoroseum, F solani, F verticillioides, Penicillium citrinum and Rhizopus stolonifer were recorded from samples ofAegle marmelos, Aesculus indica, Buchanania lanzan andPinus gerardiana. In case ofPrunus amygdalus only Rstolonifer was recorded. A significant variation in pattern of mycoflora incidence was observed in terms of source and season. Fungal
infestation in most of the substrates was found to be highest during monsoon. Aflatoxins were the most common mycotoxins elaborated
by different isolates ofA flavus obtained fromA marmelos, B lanzan andP gerardiana. The amount of aflatoxins produced by the toxigenic isolates ofA flavus was in the range of traces to 0.9–26.0 μg/ml inA marmelos, 0.8–17.5 μg/ml inP gerardiana and 0.65–13.2 μg/ml inB lanzan. The percentage toxigenicity was comparatively lower in the isolates of other mycotoxigenic fungi. Aflatoxins were detected
almost in all the samples analyzed for mycotoxin contamination. However, traces of zearalenone were detected inA marmelos. The concentration of aflatoxin B1 was in the range of 0.13–0.75 μg/g inA marmelos, 0.09–0.60 μg/g inP gerardiana and 0.01–0.20 ug/g inB lanzan. Mycotoxins were not detected inAesculus indica andPrunus amygdalus. 相似文献
10.
Adiki Shanta Kumari Perla Chandra Kiran Saha Gargi Katakam Prakash Theendra Vinaykumar 《Biological trace element research》2019,190(1):150-156
Biological Trace Element Research - This research article aims to establish the intake ratio of probiotic Lactobacillus plantarum 299v with iron supplement pearl millet by central composite design... 相似文献