Effect of culture conditions, cytokinins, methyl jasmonate and salicylic acid on the biomass accumulation and production of withanolides in multiple shoot culture of Withania somnifera (L.) Dunal using liquid culture

The influence of cytokinins and culture conditions including medium volume, harvest time and elicitation with abiotic elicitors (SA/MeJ) have been studied for the optimal production of biomass and withanolides in the multiple shoot culture of Withania somnifera. Elicitation of shoot inoculum mass (2 g l^?l FW) with SA at 100 μM in the presence of 0.6 mg l^?l BA and 20 mg l^?l spermidine for 4 h exposure time at the 4th week in 20 ml liquid medium recorded higher withanolides production (withanolides A [8.48 mg g^?l DW], withanolides B [15.47 mg g^?l DW], withaferin A [29.55 mg g^?l DW] and withanone [23.44 mg g^?l DW]), which were 1.14 to 1.18-fold higher than elicitation with MeJ at 100 μM after 5 weeks of culture. SA-elicited cultures did not exhibit much variation in biomass accumulation when compared to control. This cytokinin induces and SA-elicited multiple shoot culture protocol provides a potential alternative for the optimal production of biomass and withanolides utilizing liquid culture.     

Increased production of withanolide A, withanone, and withaferin A in hairy root cultures of Withania somnifera (L.) Dunal elicited with methyl jasmonate and salicylic acid

The utility of hairy root cultures to produce valuable phytochemicals could be improved by repartitioning more of the desired phytochemical into the spent culture media, thereby simplifying the bioprocess engineering associated with the purification of the desired phytochemical. The majority of nicotine produced by tobacco hairy root cultures is retained within roots, with lesser amounts exuded into the spent culture media. Reduced expression of the tobacco nicotine uptake permease (NUP1) results in significantly more nicotine accumulating in the media. Thus, NUP1-reduced expression lines provide a genetic means to repartition more nicotine into the culture media. The present study examined a wild type and a NUP1-reduced expression hairy root line during a variety of treatments to identify culture conditions that increased nicotine accumulation in the media. The NUP1-reduced expression line grew faster, used less oxygen, and exuded more nicotine into the media. Basification of the culture media associated with root growth resulted in a dramatic reduction in nicotine accumulation levels in the media, which was reversed by decreasing the pH of the media. Kinetic analysis of hairy root growth and nicotine accumulation in the media revealed a potential improvement in nicotine yields in the media by stimulating the branching of tobacco hairy roots.     

Synthesis,optimization, and characterization of biogenic manganese oxide (BioMnOx) by bacterial isolates from mangrove soils with sorbents property towards different toxic metals

BioMetals - Manganese oxidizing bacteria, Bacillus mycoides and Bacillus subtilis were isolated from mangrove soils and optimized for the removal of Mn(II) with simultaneous production of biogenic...     

Male–Male Relationships in Lion-tailed Macaques (<Emphasis Type="Italic">Macaca silenus</Emphasis>) and Bonnet Macaques (<Emphasis Type="Italic">Macaca radiata</Emphasis>)

Socioecology suggests that female distribution in space is determined by the distribution of food resources and the male distribution is influenced by female distribution. Though studies have traditionally focused on females, males have received increasing attention in recent years. We compared male–male relationships in lion-tailed macaques and bonnet macaques. Because bonnet macaques have a high adult male:female sex ratio and are seasonal breeders whereas lion-tailed macaques have a low adult male:female sex ratio and are largely aseasonal breeders, we predicted that bonnet macaque males would be spatially and socially more tolerant of each other and would have less linear dominance relationships than lion-tailed macaques. We recorded male–male and male–female relationships in 1 group of wild macaques of each species via scan sampling and 1–0 sampling. The results revealed that lion-tailed macaque males largely remained at a distance from each other whereas bonnet macaque males remained in close proximity to one another. Lion-tailed macaque males were more agonistic toward each other whereas bonnet macaque males showed more affiliative interactions. The dominance hierarchy among lion-tailed macaque males was more linear than among bonnet macaque males. Our data support the hypothesis that the study of spatial structuring, temporality of interactions, and linearity of social relationships may contribute to a better understanding of macaque social systems.     

Purification and characterization of manganese-dependent alkaline serine protease from Bacillus pumilus TMS55

The purification and characterization of a Mn2+-dependent alkaline serine protease produced by Bacillus pumilus TMS55 were investigated. The enzyme was purified in three steps: concentrating the crude enzyme using ammonium sulfate precipitation, followed by gel filtration and cation-exchange chromatography. The purified protease had a molecular mass of approximately 35 kDa, was highly active over a broad pH range of 7.0 to 12.0, and remained stable over a pH range of 7.5 to 11.5. The optimum temperature for the enzyme activity was found to be 60 degreesC. PMSF and AEBSF (1 mM) significantly inhibited the protease activity, indicating that the protease is a serine protease. Mn2+ ions enhanced the activity and stability of the enzyme. In addition, the purified protease remained stable with oxidants (H2O2, 2%) and organic solvents (25%), such as benzene, hexane, and toluene. Therefore, these characteristics of the protease and its dehairing ability indicate its potential for a wide range of commercial applications.     

Klf15 orchestrates circadian nitrogen homeostasis

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Highlights? Nitrogen homeostasis exhibits circadian rhythmicity in mammals ? Klf 15 regulates rhythmic amino acid utilization and ammonia detoxification ? Krüppel-like factor 15 is regulated by the circadian clock ? Feeding is a major external cue regulating Klf15 rhythmicity and nitrogen homeostasis     

Altered bioavailability of testosterone in androgen-binding protein-transgenic mice

Serum and intra-testicular total and free testosterone levels in different age groups of mice (7-360-day-old) were analyzed by radioimmunoassay (RIA) in age-matched wild type (WT)-control and in transgenic mice homozygous to rat androgen-binding protein (ABP-TG), in order to identify possible causes of increased pre-pubertal germ cell apoptosis, spermatogenetic defect and reduced fertility seen in ABP-TG mice. Total intra-testicular testosterone levels in the pre-pubertal ABP-TG (7, 14, 21 and 30-day-old) mice were significantly lower than those in age-matched WT-controls. After puberty (60 days and older) the total intra-testicular testosterone levels were higher than those in age-matched WT-controls and increased gradually, peaking on day 180. Serum total testosterone levels in ABP-TG mice did not differ from those in WT-control until day 30. However, a significant increase in the level of serum total testosterone was observed from day 60. Serum and intra-testicular free testosterone levels were significantly lower in 30, 120, 180 and 360-day-old ABP-TG mice than in age-matched WT-controls. Immunohistochemistry for the cholesterol side-chain cleavage (cytochrome P450) enzyme and quantitative real-time RT-PCR analysis of mRNAs for androgen receptor and for enzymes related to steroidogenesis did not show any changes in 30-day-old ABP-TG mice, indicating that the rates of steroidogenesis and utilization were not altered. Human chorionic gonadotrophin (hCG) administration to adult ABP-TG mice increased the intra-testicular total and free testosterone as well as total germ cell counts. We conclude that the presence of greater than physiological concentration of ABP in the mouse testis alters the ratio of free/bound testosterone, and thereby decreases the availability of free testosterone. As a result, a heightened wave of germ cell apoptosis during the pre-pubertal period followed by a reduction in germ cell numbers and reduced fertility is seen in these mice.     

Dynamics of testicular germ cell proliferation in normal mice and transgenic mice overexpressing rat androgen-binding protein: a flow cytometric evaluation

Transgenic mice carrying rat androgen-binding protein (ABP) genomic DNA express high amounts of testicular ABP and develop a progressive impairment of spermatogenesis. To understand the mechanism of these changes, we have studied the pattern of testicular germ cell proliferation from 7 to 360 days of age in wild-type (WT) control and transgenic homozygous (ABP-TG) mice by flow cytometry after labeling DNA in isolated germ cells with propidium iodide. At all ages studied, the body weight of the ABP-TG mice was lower than that of age-matched WT controls. Significantly reduced testicular weight and total germ cell number in the ABP-TG mice were evident from Day 30 and Day 60, respectively. Flow cytometric analysis of isolated germ cells revealed that the number of germ cells undergoing proliferation (S-phase cells) was identical in WT control and ABP-TG mice up to Day 14. Subsequently, the number of germ cells in S-phase was consistently higher in ABP-TG than in WT mice. The number of primary spermatocytes was significantly increased starting from Day 60, and the numbers of round and elongated spermatids were significantly reduced in the ABP-TG animals from Day 21 and Day 60 onwards, respectively. Immunocytometry for intracellular ABP at 90 days of age revealed that the percentage of ABP-containing germ cells was greater in ABP-TG than in WT mice. The continuous presence of ABP in mouse seminiferous tubules at greater than physiological concentrations facilitates the formation of primary spermatocytes but impairs subsequent transformation to round and elongated spermatids. Based on our observations and the analysis of the available literature, the most likely mechanism for production of these effects is sustained reduction in the bioavailability of androgens.     

Advances in understanding the mechanism of resistance to anthracnose and induced defence response in tea plants

The tea plant (Camellia sinensis) is susceptible to anthracnose disease that causes considerable crop loss and affects the yield and quality of tea. Multiple Colletotrichum spp. are the causative agents of this disease, which spreads quickly in warm and humid climates. During plant–pathogen interactions, resistant cultivars defend themselves against the hemibiotrophic pathogen by activating defence signalling pathways, whereas the pathogen suppresses plant defences in susceptible varieties. Various fungicides have been used to control this disease on susceptible plants, but these fungicide residues are dangerous to human health and cause fungicide resistance in pathogens. The problem-solving approaches to date are the development of resistant cultivars and ecofriendly biocontrol strategies to achieve sustainable tea cultivation and production. Understanding the infection stages of Colletotrichum, tea plant resistance mechanisms, and induced plant defence against Colletotrichum is essential to support sustainable disease management practices in the field. This review therefore summarizes the current knowledge of the identified causative agent of tea plant anthracnose, the infection strategies and pathogenicity of C. gloeosporioides, anthracnose disease resistance mechanisms, and the caffeine-induced defence response against Colletotrichum infection. The information reported in this review will advance our understanding of host–pathogen interactions and eventually help us to develop new disease control strategies.