(C) Pyruvate metabolism is either active or up-regulated in darkness As shown in Figure 4, the expression level of genes presumed to carry out pyruvate metabolism during chemotrophic

growth is either up-regulated, such as porA (HM1_0807, encoding PFOR; 4-8 fold increase), or not affected, as in the case for fdxR (HM1_0289, encoding ferredoxin (Fd)-NADP+ oxidoreductase (FNR)) and two adjacent ferredoxin genes, fdx (HM1_1461) and pshB (HM1_1462). Despite the lack of genes encoding pyruvate dehydrogenase, PFOR can be an alternative enzyme for converting pyruvate into acetyl-CoA and Fdred in pyruvate fermentation (equation 1), and Fdred can interact with FNR, known to be the last electron transporter in the light-induced electron transfer chain, to produce NADPH (equation 2). (2) Note that high FNR activity (10 μmole/min•mg BACE inhibitor {Selleck Anti-infection Compound Library|Selleck Antiinfection Compound Library|Selleck Anti-infection Compound Library|Selleck Antiinfection Compound Library|Selleckchem Anti-infection Compound Library|Selleckchem Antiinfection Compound Library|Selleckchem Anti-infection Compound Library|Selleckchem Antiinfection Compound Library|Anti-infection Compound Library|Antiinfection Compound Library|Anti-infection Compound Library|Antiinfection Compound Library|Anti-infection Compound Library|Antiinfection Compound Library|Anti-infection Compound Library|Antiinfection Compound Library|Anti-infection Compound Library|Antiinfection Compound Library|Anti-infection Compound Library|Antiinfection Compound Library|Anti-infection Compound Library|Antiinfection Compound Library|Anti-infection Compound Library|Antiinfection Compound Library|Anti-infection Compound Library|Antiinfection Compound Library|buy Anti-infection Compound Library|Anti-infection Compound Library ic50|Anti-infection Compound Library price|Anti-infection Compound Library cost|Anti-infection Compound Library solubility dmso|Anti-infection Compound Library purchase|Anti-infection Compound Library manufacturer|Anti-infection Compound Library research buy|Anti-infection Compound Library order|Anti-infection Compound Library mouse|Anti-infection Compound Library chemical structure|Anti-infection Compound Library mw|Anti-infection Compound Library molecular weight|Anti-infection Compound Library datasheet|Anti-infection Compound Library supplier|Anti-infection Compound Library in vitro|Anti-infection Compound Library cell line|Anti-infection Compound Library concentration|Anti-infection Compound Library nmr|Anti-infection Compound Library in vivo|Anti-infection Compound Library clinical trial|Anti-infection Compound Library cell assay|Anti-infection Compound Library screening|Anti-infection Compound Library high throughput|buy Antiinfection Compound Library|Antiinfection Compound Library ic50|Antiinfection Compound Library price|Antiinfection Compound Library cost|Antiinfection Compound Library solubility dmso|Antiinfection Compound Library purchase|Antiinfection Compound Library manufacturer|Antiinfection Compound Library research buy|Antiinfection Compound Library order|Antiinfection Compound Library chemical structure|Antiinfection Compound Library datasheet|Antiinfection Compound Library supplier|Antiinfection Compound Library in vitro|Antiinfection Compound Library cell line|Antiinfection Compound Library concentration|Antiinfection Compound Library clinical trial|Antiinfection Compound Library cell assay|Antiinfection Compound Library screening|Antiinfection Compound Library high throughput|Anti-infection Compound high throughput screening| protein) is detected in the cell free extract of H. modesticaldum (Additional file 5: Figure S4). Consistent with the studies of FNR from other organisms, we also detected that FNR in H. modesticaldum has higher specificity for NADPH versus NADH, and that the reaction turnover for producing

Fdred, by measuring the formation of NADP+ or NAD+ (equation 2), is more than 50-fold faster for NADPH than for NADH (Additional file 5: Figure S4A). The rate of NADPH oxidation is accelerated with addition

of ferricyanide (Additional file 5: Figure S4B). Together, the discovery of FNR activity in cell extracts indicates that ifoxetine the reducing power required for carbon and nitrogen metabolisms in H. modesticaldum can be generated from FNR during phototrophic and chemotrophic growth. (D) Photosynthetic pigments produced in darkness The genomic information indicates that H. modesticaldum has the simplest (bacterio)chlorophyll biosynthesis pathway compared to other sequenced photosynthetic bacteria. A putative mechanism of BChl g biosynthesis was recently proposed [1]. The biosynthesis of photosynthetic pigments during chemotrophic growth under nitrogen fixing conditions has been observed for some species of heliobacteria, including Heliobacillus mobilis, Heliobacterium gestii and Heliobacterium chlorum [21]. Here, we would like to examine if H. modesticaldum can also produce (B)Chls in darkness. Figure 6 shows the normalized absorption spectra of the intact cell cultures from phototrophic and chemotrophic growth, after cell light-scattering has been digitally subtracted from the raw data (see Methods). The absorption peaks of the unique pigment BChl g at 788 nm and of 81-OH-Chl a F at 670 nm can be detected in Figure 6, indicating that photosynthetic pigments can be produced by H. modesticaldum during chemotrophic growth.