Proteins carotenes

Aleurites moluceanu (L.) Willd. Shi Li (China wood oil) (bark, seed) Protein, carotene, thiamine.50 This herb is toxic. As poultice for fever, headache, swollen joints, and ulcer. 

Food. In Bangladesh, Thailand, and Sri Lanka, the leaves are sold as a leafy vegetable, rich in digestible protein, carotene, and vitamin C. ... 

FIGURE 17 11 Imine formation between the aldehyde function of 11 as retinal and an ammo group of a protein (opsin) is involved in the chemistry of vision The numbering scheme in retinal is specifically developed for carotenes and related compounds... 

Two classes of antioxidants are known the low-molecular weight compounds (tocopherols, ascorbate, -carotene, glutathione, uric acid and etc.) and the proteins (albumin, transferrin, caeruloplasmin, ferritin, etc.) including antioxidant enzymes (e.g. superoxide dismutase, catalase, glutathione peroxidase). 

The carotenoids are located in photosynthetic pigment-protein complexes (PPCs) in the thylakoid membranes (Young, 1993), with minor amounts in the chloroplast envelope (Joyard et al, 1991) and the envelope of amyloplasts (Fishwick and Wright, 1980). In all plastid envelope membranes, violaxanthin is the major carotenoid. Carotenes are also found in plastoglobuli (Lichtenthaler and Peveling, 1966). 

PALOZZA P, SERINI S, MAGGIANO N, ANGELINI M, BONINSEGNA A, DI NICUOLO F, RANELLETTI F O and CALVIELLO G (2002) Induction of cell cycle arrest and apoptosis in human colon adenocarcinoma cell lines by P-carotene through down-regulation of cyclin A and Bcl-2 family proteins , Carcinogenesis, 23, 11-18. 

The chlorophyU-protein complexes located in the hydrophobic thylakoid membrane are accompaified by xanthophyUs, certain carotenes, and tocopherols (depend-... 

Typically several different carotenoids occur in plant tissues containing this class of pigments. Carotenoids are accumulated in chloroplasts of all green plants as mixtures of a- and P-carotene, P-cryptoxanthin, lutein, zeaxanthin, violaxanthin, and neoxanthin. These pigments are found as complexes formed by noncovalent bonding with proteins. In green leaves, carotenoids are free, nonesterified, and their compositions depend on the plant and developmental conditions. In reproductive... 

Recent findings from the ATBC stndy even showed that P-carotene snpple-mentation increased the post-trial risk of a hrst-ever non-fatal MI. Two secondary prevention trials, the Heart Protection Stndy and the ATBC presented similar resnlts. The former showed no association between P-carotene and fatal or non-fatal vascular events and the latter reported signihcantly increased risks of fatal coronary events in the P-carotene-snpplemented gronp. Resnlts of clinical trials focused on the effects of carotenoids on CVD biomarkers are controversial. Although carotenoid supplementation increased sernm levels,only lycopene was shown to be inversely associated with lipid, protein, DNA and LDL oxidation, and plasma cholesterol levels. - - ... 

In contrast, the carotenes such as p-carotene and lycopene may position themselves parallel to the membrane surfaces to remain in a more lipophilic environment in the inner cores of the bilayer membranes. To move through an aqueous environment, carotenoids can be incorporated into lipid particles such as mixed micelles in the gut lumen or lipoproteins in the blood circulation and they can also form complexes with proteins with unspecific or specific bindings. 

FIGURE 3.2.2 Metabolic pathways of carotenoids such as p-carotene. CM = chylomicrons. VLDL = very low-density lipoproteins. LDL = low-density lipoproteins. HDL = high-density lipoproteins. BCO = p-carotene 15,15 -oxygenase. BCO2 = p-carotene 9, 10 -oxygenase. LPL = lipoprotein lipase. RBP = retinol binding protein. SR-BI = scavenger receptor class B, type I. 

Gugger, E.T. and Erdman, J.W., Intracellular (3-carotene transport in bovine liver and intestine is not mediated by cytosolic proteins, J. Nutr, 126, 1470, 1996. 

Tibaduiza, E.C. et al., Excentric cleavage products of beta-carotene inhibit estrogen receptor positive and negative breast tumor cell growth in vitro and inhibit activator protein-1-mediated transcriptional activation, J. Nutr., 132, 1368, 2002. 

Wang, X.D. et al., Retinoid signaling and activator protein-1 expression in ferrets given beta-carotene supplements and exposed to tobacco smoke, J. Natl. Cancer Inst., 91, 60, 1999. 

Mammals lack the ability to synthesize astaxanthin or convert dietary astaxanthin into vitamin A. Unlike p-carotene, astaxanthin has no pro-vitamin activity in these animals. Astaxanthin has been shown in both in vitro and in a study with human subjects to be effective for the prevention of the oxidation of low-density protein, suggesting that it can be used to prevent arteriosclerosis, coronary artery disease, and ischemic brain development. A number of astaxanthin health products are under study. 

Orange carotenoid protein Conserved hypothetical protein (sir 1964) ft- OCP N terminal domain OCP C-terminal domain Hypothetical protein Hypothetical protein D- Beta carotene ketolase homolog Hydrolase... 

Nucleic acids are not the only biomolecules susceptible to damage by carotenoid degradation products. Degradation products of (3-carotene have been shown to induce damage to mitochondrial proteins and lipids (Siems et al., 2002), to inhibit mitochondrial respiration in isolated rat liver mitochondria, and to induce uncoupling of oxidative phosphorylation (Siems et al., 2005). Moreover, it has been demonstrated that the degradation products of (3-carotene, which include various aldehydes, are more potent inhibitors of Na-K ATPase than 4-hydroxynonenal, an aldehydic product of lipid peroxidaton (Siems et al., 2000). 

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