China
Africa
Explore chapters and articles related to this topic
Microalgal Pigments as Natural Color
Published in Hafiz Ansar Rasul Suleria, Megh R. Goyal, Masood Sadiq Butt, Phytochemicals from Medicinal Plants, 2019
K. G. Sreekala, Malairaj Sathuvan, Javee Anand, Karuppan Ramamoorthy, Vengatesh Babu, S. Nagaraj
Zeaxanthin is an orange-yellow carotenoid pigment (xanthophyll), found in the microalgal species, Botryococcus braunii, Dunaliella salina, Nannochloropsis oculata, and Nannochloropsis gaditana, and is commercially used as food additive E 161 h, animal feed, pharmaceuticals for colon cancer, and eye health.27 There are number of reports on the antioxidant capacity of Dunaliella, Botryococcus, Chlorella, Nostoc, Arthrospira, Phaeodactylum, Polysiphonia, Scytosiphon, and Synechocystis.
Potentials and Challenges in the Production of Microalgal Pigments with Reference to Carotenoids, Chlorophylls, and Phycobiliproteins
Published in Gokare A. Ravishankar, Ranga Rao Ambati, Handbook of Algal Technologies and Phytochemicals, 2019
Delia B. Rodriguez-Amaya, Iriani R. Maldonade
Statistical optimization of four variables (nitrate, phosphate, pH, and light intensity) increased the maximum phycobiliprotein contents in Synechocystis sp. PCC 6701 over 400% (Hong and Lee, 2008). Low light intensity and high initial biomass concentration led to increased C-phycocyanin accumulation in Spirulina (Xie et al., 2015). Fed-batch cultivation proved to be an effective strategy to further enhance C-phycocyanin production, which also required nitrogen-sufficient condition and other nutrients. Biomass production and phycocyanin accumulation were enhanced in Spirulina in fed-batch cultivation by adding sodium glutamate and succinic acid (Manirafasha et al., 2018).
Carbon Dioxide Sequestration by Microalgae
Published in Gokare A. Ravishankar, Ranga Rao Ambati, Handbook of Algal Technologies and Phytochemicals, 2019
G.V. Swarnalatha, Ajam Shekh, P.V. Sijil, C.K. Madhubalaji, Vikas Singh Chauhan, Ravi Sarada
There are five classes of CA, i.e., α, β, γ, δ, and ε (Shekh et al. 2013; So and Espie 2005). The α-class was found in animals, plants, and eubacteria. They are protein monomers with antiparallel β-strands with active site (Liljas et al. 1972; So and Espie 2005). Active site majorly contains hydrophobic amino acid side chains with Zn2+ ion coordinated by three histidine residues (Liljas et al. 1972). β-CAs were found in chloroplasts of plants and sub-cellular compartments of many organisms. The amino acids present in β-CAs are different than in α-CAs. β-CAs are active only when they oligomerize and the catalytic core of a β-CA can be dimer, tetramer, or octamer (Mitsuhashi et al. 2000). The hydrophobic site resulted from dimerization serves as active site for CO2 binding. The central metal Zn2+ is surrounded by a combination of His, Cys, and Glu residues (Mitsuhashi et al. 2000). The α-helical structures are present in β-CAs. The γ-CA was first isolated from methanogenic archaeon Methano sarcinathermophila (Shekh 2012). Cam (for carbonic anhydrase of M. thermophile), a type of γ-CA from M. thermophile, is active when it is trimerized (Kisker et al. 1996). Each monomer resembles a triangle when it is cross-sectioned. The αβ-helix was found in γ-CA where β-helix was a left-handed structure containing seven complete turns with an α-helix at the end (Kisker et al. 1996). The active sites are present at the interface of two β-helices. The interface is stabilized by hydrogen bonds, salt bridges, and hydrophobic interactions. Among γ-CAs, cam is the only one which shows CA activity. Several cam homologs of plants and bacteria lack CA activity. These include cytochrome C maturation operon (CcmM), a γ class CA from the cyanobacteria Synechocystis PCC6803, and Synechococcus PCC7942. The δ-class (TWCA1) is found in marine diatom Thalassiosira weissflogii (Roberts et al. 1997). Chlamydomonas reinhardtii has five classes of CAs, out of which three α-CAs and two β-CAs are identified (Moroney et al. 2001).
Biofilm diversity, structure and matrix seasonality in a full-scale cooling tower
Published in Biofouling, 2018
L. Di Gregorio, R. Congestri, V. Tandoi, T. R. Neu, S. Rossetti, F. Di Pippo
Autumn assemblages (Bi-Au) were dominated by Alphaproteobacteria (40.9%) with the highest contribution from the Rhodobacteraceae (11.0%), Acetobacteraceae (10.3%), Nordellaceae (5.2%), Hyphomicrobiaceae (3.8%) and Sphingomonadaceae (3.4%). Cyanobacteria were also abundant, accounting for 32.6% of the total OTUs. Within this group, most sequences were attributed to the undetermined OUT_13 (13.9%) and to the filamentous Leptolyngbya (4.6%) sp. and the coccal Cyanobium sp. (4.5%) (Figure 2). In addition, light microscope observations showed cyanobacterial populations of filamentous Microcoleus sp., Phormidium spp., Nostoc sp. and Calothrix sp., and the coccal genera Cyanothece, Pleurocapsa and Synechocystis. OTUs affiliated to chloroplasts (4.1%) were associated to Vischeria sp., Kirchneriella sp. and Scenedesmus sp. Within diatoms, Navicula and Nitzschia species were found (Figure 3D).
Therapeutic targets for the treatment of microsporidiosis in humans
Published in Expert Opinion on Therapeutic Targets, 2018
Methionine aminopeptidase (MetAPs) activity is essential for eukaryotic cell survival as the removal of the terminal methionine of a protein is often critical for its function and post-translational modification. Two major classes of MetAPs, designated type 1 and type 2 (MetAP1 and MetAP2), were originally identified as cytosolic proteins in eukaryotes [134–136]. In the genome of the cyanobacterium, Synechocystis sp., a novel MetAP3 gene was also identified [137]. MetAP2, as a member of the dimetallohydrolase family, is a cytosolic metalloenzyme that catalyzes the hydrolytic removal of N-terminal methionine residues from nascent proteins [138–140]. Important functions of this enzyme, which is found in all organisms, are its role in tissue repair and protein degradation, as well as the role it plays in angiogenesis [139,141]. The MetAP2 genes were identified from the human pathogenic microsporidia Enc. intestinalis, Enc. hellem, Enc. cuniculi, Ent. bieneusi, and A. algerae using the strategy of homology cloning by polymerase chain reaction [142–144]. Based on genome sequence data (Microsporidiadb.org), microsporidia appear to only contain MetAP2 [145]. Since both MetAP1 and MetAP2 genes exist in mammalian genomes and the functions of these two MetAP genes overlap, this makes microsporidia MetAP2 an essential gene in microsporidia and a logical target for designing therapeutic agents for microsporidiosis [144].
Chaperonomics in leptospirosis
Published in Expert Review of Proteomics, 2018
Arada Vinaiphat, Visith Thongboonkerd
An attempt has been made to identify sHSPs-interacting partners in Synechocystis sp. PCC 6803 during heat stress [53]. Some of the Hsp16.6-interacting partners identified from this study have been shown to play roles in various cellular processes, including transcription, translation, cell signaling, and secondary metabolism [53]. Among well recognized bacterial species, E. coli and M. tuberculosis contain only two copies of genes encoding sHSPs, whereas B. subtilis contains three copies of such genes [50]. In E. coli, the two sHSPs (IbpA and IbpB) are associated with inclusion bodies and aggregates that are formed during heat stress [54,55]. After binding, IbpA alone can reduce size of the inclusion bodies and/or aggregates [56]. Together with IbpB, these two sHSPs can facilitate Hsp100/Hsp70-mediated function to disaggregate or further reduce size of the protein aggregates [56].Genomic analysis of 15 bacteria representing a wide variety of prokaryotic lineages has shown that eight of the bacterial genomes do not contain sHSPs-related sequences [50]. Interestingly, the absence of sHSPs has been found mostly in the pathogenic bacteria [57]. However, it is challenging to address why sHSPs are dispensable in some pathogenic bacteria and why symbiotic bacteria (i.e. Bradyrhizobium japonicum) have as many as 12 sHSPs [58].