A world of cytochrome P450s Nelson, David R.
Philosophical transactions of the Royal Society of London. Series B. Biological sciences,
02/2013, Volume:
368, Issue:
1612
Journal Article
Peer reviewed
Open access
The world we live in is a biosphere influenced by all organisms who inhabit it. It is also an ecology of genes, with some having rather startling effects. The premise put forth in this issue is ...cytochrome P450 is a significant player in the world around us. Life and the Earth itself would be visibly different and diminished without cytochrome P450s. The contributions to this issue range from evolution on the billion year scale to the colour of roses, from Darwin to Rachel Carson; all as seen through the lens of cytochrome P450.
Rose has been entwined with human culture and history. “Blue rose” in English signifies unattainable hope or an impossible mission as it does not exist naturally and is not breedable regardless of ...centuries of effort by gardeners. With the knowledge of genes and enzymes involved in flower pigmentation and modern genetic technologies, synthetic biologists have undertaken the challenge of producing blue rose by engineering the complicated vacuolar flavonoid pigmentation pathway and resulted in a mauve-colored rose. A completely different strategy presented in this study employs a dual expression plasmid containing bacterial idgS and sfp genes. The holo-IdgS, activated by Sfp from its apo-form, is a functional nonribosomal peptide synthetase that converts l-glutamine into the blue pigment indigoidine. Expression of these genes upon petal injection with agro-infiltration solution generates blue-hued rose flowers. We envision that implementing this proof-of-concept with obligatory modifications may have tremendous impact in floriculture to achieve a historic milestone in rose breeding.
From 1970 until 1974, the Council on Interracial Children’s Books (CIBC) ran the Arts and Storytelling in the Streets program throughout New York City. This program involved African American and ...Puerto Rican artists and storytellers bringing children’s literature directly to children in the streets. This occurred amid a rise in African American children’s literature and educational upheavals in the city as local communities demanded oversight of their schools. Originating in the Ocean Hill-Brownsville district in New York City, the Arts and Storytelling on the Streets program helps to underscore the interrelation between African American children’s literature and educational activism. This article examines how storytelling sessions run by authors and illustrators became extensions of African American children’s literature and educational activism in the city as Black American children’s books became key tools in a fight for a more representative and relevant education. Storytelling teams hoped to use African American children’s literature to help engage children in reading and provide a positive association with literature among local children. The Art and Storytelling program mirrored ideas and themes within African American children’s literature including Black pride, community strength, and resisting white supremacy. The program also became a key extension of the literature as the locations, storytellers, and the audiences all helped to expand upon the impact and many meanings inherent in contemporary African American children’s literature.
Flowers of the rose cultivar Rhapsody in Blue display unusual colors, changing as they age, from a vivid red-purple to a lighter and duller purple, which are based on tonalities corresponding to hue ...angles between 340 and 320° in the CIELAB scale. Unexpectedly, the chemical basis of these colors is among the simplest, featuring cyanin (cyanidin 3,5-di-O-glucoside), the most frequent anthocyanin in flowers, as the sole pigment and quercetin kaempferol glycosides as copigments at a relatively low copigment/pigment ratio (about 3/1), which usually produces magenta or red shades in roses. This color shift to bluer shades is coupled with the progressive accumulation of cyanin into vacuolar anthocyanic inclusions (AVIs), the occurrence of which increases as the petals grow older. In addition to the normal λmax of cyanin at ∼545 nm, the transmission spectra of live petals and of epidermal cells exhibit a second λmax in the 620−625 nm range, the relative importance increasing with the presence of AVIs. In petals of fully opened flowers, the only pigmented structures in the vacuoles of epidermal cells are AVIs; their intense and massive absorption in the 520−640 nm area produces a much darker and bluer color than measured for the vacuolar solution present at the very first opening stage. Cyanin is probably “trapped” into AVIs at higher concentrations than would be possible in a vacuolar solution and in quinonoidal form, appearing purple-blue because of additional absorption in the 580−630 nm area. Quite similar pigmentation features were found in very ancient rose cultivars (cv. L'Evêque or Bleu Magenta), also displaying this type of so-called “blue” color. Keywords: Blue rose; cyanin; anthocyanic vacuolar inclusions (AVI); flower color
In this story based on an incident from the life of astronaut Ron McNair, nine-year-old Ron walks into his local public library with a mission - to secure a library card for himself so that he can ...take books home to read. Because it's 1959 and segregation laws prohibit African Americans from borrowing books, Ron is at first declined.
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