The retinylidene chromophore mutant (Y185F) of bacteriorhodopsin, in which Tyr-185 is substituted by phenylalanine, is examined and compared with wild-type bacteriorhodopsin expressed in Escherichia coli; both were reinstituted similarly in vesicles. The Y185F mutant shows (at least) two distinct spectra at neutral pH. Upon light absorption, the blue species (which absorbs in the red) behaves a...

Tree tomato fruits from the yellow giant, giant purple and New Zealand purple cultivars, cultivated in Ecuador were analysed for their phenolic composition and antioxidant capacity. Twelve hydroxycinnamoyl derivatives and four anthocyanins (in the purple cultivars) were detected and identified. The hydroxycinnamoyl derivatives mostly derived from caffeic acid, being 3-O-caffeoylquinic acid and ...

Purple rice (Oryza sativa L. var. indica) cv. Kum Doisaket is cultivated in northern Thailand. This study evaluated the mutagenic and antimutagenic properties of hydrophilic and lipophilic components of purple rice using the Ames test. The seed and hull of purple rice were extracted with hexane, methanol, ethanol, and water. The methanol extracts had the highest amounts of phenolic acids and fl...

Background and Aim: One of the key aspects of maternal care is observing the progress of labor. Careful assessment of labor progress could provide mothers to be referred on time and could decrease the maternal and neonatal morbidity. This study aimed to compare diagnostic accuracy of purple line with transvers diagonal of Michaelis sacral rhomboid to predict labor progress in nulliparous and mu...

Anthocyanins from purple sweet potatoes can serve as natural colorants due to their high heat and light stability and are commonly used in juices, alcoholic beverages, jams, confectioneries, bread, snacks and noodles. There are several commercially available varieties of purple sweet potatoes, which can vary in storage root size, shape, and color. During the last decade sweet potato cultivars w...

The dogwhelk is a rocky intertidal gastropod of the North Nucella lapillus Atlantic coast. Individual shell color varies. Common colors range between white and brown, with darker dogwhelks being more affected by heat stress than lighter-colored conspecifics. Other reported shell colors are purple, black, mauve, pink, yellow, and orange from UK coasts, red and gray from the Bay of Fundy coast of...

There is a relative absence of studies dealing with mats of purple sulphur bacteria in the intertidal zone. These bacteria display an array of metabolic pathways that allow them to disperse and develop under a wide variety of conditions, making these mats important in terms of ecosystem processes and functions. Mass blooms of purple sulphur bacteria develop during summer on sediments in the int...

1. Carotenoids have been identified and their quantities measured in the eyes of several frog species. The combined pigment epithelium and choroid layer of an R. pipiens or esculenta eye contain about 1gamma of xanthophyll and about 4gamma of vitamin A. During light adaptation the xanthophyll content falls 10 to 20 per cent. 2. Light adapted retinas contain about 0.2-0.3 gamma of vitamin A alon...

The purple membrane ofHalobacterium halobium contains a single protein known as bacteriorhodopsin, which is composed of 1 mol retinal]mol bacterio-opsin [ 1 ]. The organization of the protein within each purple membrane sheet is that of an exact 2-dimensional crystal. X-ray and electron diffraction data have revealed that the bacteriorhodopsin in purple membrane is arranged as trimeric units in...

The purple leaf pigmentation mainly associated with anthocyanins accumulation is common in Brassica but the mechanisms of its production and its potential physiological functions are poorly understood. Here, we performed the phenotypic, cytological, physiological, and comparative leaves transcriptome analyses of 11 different varieties belonging to five Brassica species with purple or green leav...