Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0038187 (starvation)
 24,951 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Among the 118 genes upregulated by Pseudomonas aeruginosa in response to iron starvation [Ochsner, U. A., Wilderman, P. J., Vasil, A. I., and Vasil, M. L. (2002) Mol. Microbiol. 45, 1277-1287], we focused on the products of the two genes encoding electron transfer proteins, as a means of identifying the redox partners of the heme oxygenase (pa-HO) expressed under low-iron stress conditions. Biochemical and spectroscopic investigations demonstrated that the bfd gene encodes a 73-amino acid protein (pa-Bfd) that incorporates a [2Fe-2S]2+/+ center, whereas the fpr gene encodes a 258-residue NADPH-dependent ferredoxin reductase (pa-FPR) that utilizes FAD as a cofactor. In vitro reconstitution of pa-HO catalytic activity with the newly characterized proteins led to the surprising observation that pa-FPR efficiently supports the catalytic cycle of pa-HO, without the need of a ferredoxin. In comparison, electron transfer from pa-Bfd to pa-HO is sluggish, which strongly argues against the possibility that the seven electrons needed by pa-HO to degrade biliverdin are transferred from NADPH to pa-HO in a ferredoxin (Bfd)-dependent manner. Given that pa-HO functions to release iron from exogenous heme acquired under iron-starvation conditions, the use of a flavoenzyme rather than an iron-sulfur center-containing protein to support heme degradation is an efficient use of resources in the cell. The crystal structure of pa-FPR (1.6 A resolution) showed that its fold is comparable that of the superfamily of ferredoxin reductases and most similar to the structure of Azotobacter vinelandii FPR and Escherichia coli flavodoxin reductase. The latter two enzymes interact with distinct redox partners, a ferredoxin and a flavodoxin, respectively. Hence, findings reported herein extend the range of redox partners recognized by the fold of pa-FPR to include a heme oxygenase (pa-HO).
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PMID:Biochemical and structural characterization of Pseudomonas aeruginosa Bfd and FPR: ferredoxin NADP+ reductase and not ferredoxin is the redox partner of heme oxygenase under iron-starvation conditions. 1791 50

Sebocyte differentiation is a continuous process, but its potential molecular mechanism remains unclear. We aimed to establish a novel sebocyte differentiation model using human primary sebocytes and to identify the expression profiles of differentiation-associated proteins. Primary human sebocytes were cultured on Sebomed medium supplemented with 2% serum for 7 days. Flow cytometry showed that S phase cells were decreased time-dependently, while G1 and subG1 (apoptosis) phase cells increased under serum starvation. Transmission electron microscopy and Oil Red O staining revealed a gradual increase of intracellular lipid accumulation. Expression of proliferation marker was diminished, while expression of differentiation, apoptosis, and lipogenic markers elevated gradually during 7-day culture. iTRAQ analysis identified 3582 expressed proteins in this differentiation model. Compared with day 0, number of differentially expressed proteins was 132, 54, 321, and 96 at days 1, 3, 5, and 7, respectively. Two overexpressed proteins (S100 calcium binding protein P and ferredoxin reductase) and 2 downexpressed proteins (adenosine deaminase and keratin 10) were further confirmed by Western blot and immunohistochemistry.
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PMID:Differentiation Model Establishment and Differentiation-Related Protein Screening in Primary Cultured Human Sebocytes. 2985 May 53