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1. Analysis of biosynthetic fluctuations of cultured Taxus seedlings using a metabolomic approach

Author:
Ken Tanaka; Feng Li; Kouhei Morikawa; Takahiro Nobukawa; Shigetoshi Kadota
Source:
Phytochemistry 2011 v.72 no.14-15 pp. 1760-1766
ISSN:
0031-9422
Subject:
Taxus; biosynthesis; high performance liquid chromatography; ions; metabolomics; seedlings; spectroscopy
Abstract:
... Fluctuations in the biosynthesis of taxoids in 1–5year old cultured seedlings of Taxus chinensis var. mairei were investigated using LC–IT-TOF-MS and a metabolomics approach. In the total ion chromatogram (TIC) of the extracts, 16 prominent peaks were observed. Ten compounds were identified by comparison of retention times and MS/MS spectra with those of reference compounds. An additional 6 taxoid ...
DOI:
10.1016/j.phytochem.2011.06.003
PubMed:
21762939

2. Avenolide, a Streptomyces hormone controlling antibiotic production in Streptomyces avermitilis

Author:
Shigeru Kitani; Kiyoko T. Miyamoto; Satoshi Takamatsu; Elisa Herawati; Hiroyuki Iguchi; Kouhei Nishitomi; Miho Uchida; Tohru Nagamitsu; Satoshi Omura; Haruo Ikeda; Takuya Nihira
Source:
Proceedings of the National Academy of Sciences of the United States of America 2011 v.108 no.39 pp. 16410-16415
ISSN:
0027-8424
Subject:
Gram-positive bacteria; Streptomyces avermitilis; Streptomyces fradiae; Streptomyces ghanaensis; Streptomyces griseoaurantiacus; acyl coenzyme A; anthelmintics; antibiotics; biosynthesis; chemical analysis; genes; hormones; sales; spectroscopy; stereochemistry; synthesis
Abstract:
... Gram-positive bacteria of the genus Streptomyces are industrially important microorganisms, producing >70% of commercially important antibiotics. The production of these compounds is often regulated by low-molecular-weight bacterial hormones called autoregulators. Although 60% of Streptomyces strains may use γ-butyrolactone–type molecules as autoregulators and some use furan-type molecules, little ...
DOI:
10.1073/pnas.1113908108
PubMed:
21930904
PubMed Central:
PMC3182739

3. Biosynthesis and characterization of CdS quantum dots in genetically engineered Escherichia coli

Author:
Congcong Mi; Yanyan Wang; Jingpu Zhang; Huaiqing Huang; Linru Xu; Shuo Wang; Xuexun Fang; Jin Fang; Chuanbin Mao; Shukun Xu
Source:
Journal of biotechnology 2011 v.153 no.3-4 pp. 125-132
ISSN:
0168-1656
Subject:
Escherichia coli; X-radiation; X-ray diffraction; anion exchange; bacteria; biosynthesis; biotechnology; energy; freeze-thaw cycles; genes; genetically engineered microorganisms; image analysis; luminescence; quantum dots; spectroscopy; transmission electron microscopy
Abstract:
... Quantum dots (QDs) were prepared in genetically engineered Escherichia coli (E. coli) through the introduction of foreign genes encoding a CdS binding peptide. The CdS QDs were successfully separated from the bacteria through two methods, lysis and freezing–thawing of cells, and purified with an anion-exchange resin. High-resolution transmission electron microscopy, X-ray diffraction, luminescen ...
DOI:
10.1016/j.jbiotec.2011.03.014
PubMed:
21458508
PubMed Central:
PMC3102602

4. Biosynthesis of proteins containing modified lysines and fluorescent labels using non-natural amino acid mutagenesis

Author:
Yasunori Tokuda; Takayoshi Watanabe; Kazushi Horiike; Kaori Shiraga; Ryoji Abe; Norihito Muranaka; Takahiro Hohsaka
Source:
Journal of bioscience and bioengineering 2011 v.111 no.4 pp. 402-407
ISSN:
1389-1723
Subject:
Escherichia coli; amino acids; aminoacylation; biosynthesis; calmodulin; enzymes; fluorescence; histones; mutagenesis; spectroscopy; streptavidin; suppressor genes; transfer RNA; translation (genetics)
Abstract:
... The preparation of posttranslationally modified proteins is required to investigate the function and structure of modified proteins. However, homogeneously modified proteins are not easily isolated from natural sources or prepared using modification enzymes. Non-natural amino acid mutagenesis has enabled us to incorporate modified amino acids into specific positions of proteins in both cell-free a ...
DOI:
10.1016/j.jbiosc.2010.12.012

5. Biosynthesis of silver, gold and bimetallic nanoparticles using the filamentous fungus Neurospora crassa

Author:
E. Castro-Longoria; Alfredo R. Vilchis-Nestor; M. Avalos-Borja
Source:
Colloids and surfaces 2011 v.83 no.1 pp. 42-48
ISSN:
0927-7765
Subject:
Neurospora crassa; X-radiation; aqueous solutions; biomass; biosynthesis; colloids; energy efficiency; energy-dispersive X-ray analysis; environmental impact; fungi; gold; ions; nanoparticles; nanosilver; scanning electron microscopy; silver; silver nitrate; spectroscopy; transmission electron microscopy; waste reduction
Abstract:
... The development of production processes that can reduce the environmental impact, offer waste reduction and increase energy efficiency is an important step in the field of application of nanotechnology. In this work the filamentous fungus Neurospora crassa was screened and found to be successful for the production of mono and bimetallic Au/Ag nanoparticles (NPs). Analysis by scanning electron micr ...
DOI:
10.1016/j.colsurfb.2010.10.035

6. Kinemage of action – Proposed reaction mechanism of glutamate-1-semialdehyde aminomutase at an atomic level

Author:
John L. Sorensen; Jörg Stetefeld
Source:
Biochemical and biophysical research communications 2011 v.413 no.4 pp. 572-576
ISSN:
0006-291X
Subject:
X-ray diffraction; absorption; active sites; biosynthesis; nitrogen; spectroscopy; transamination
Abstract:
... Glutamate-1-semialdehyde aminomutase (GSAM), a key enzyme in tetrapyrrole cofactor biosynthesis, performs a unique transamination on a single substrate. The substrate, glutamate-1-semialdehyde (GSA), undergoes a reaction that exchanges the position of an amine and a carbonyl group to produce 5-aminolevulinic acid (ALA). This transamination reaction is unique in the fact that is does not require an ...
DOI:
10.1016/j.bbrc.2011.09.003

7. Mechanistic enzymology of serine palmitoyltransferase

Author:
Hiroko Ikushiro; Hideyuki Hayashi
Source:
Biochimica et biophysica acta 2011 v.1814 no.11 pp. 1474-1480
ISSN:
1878-1454
Subject:
biosynthesis; pyridoxal phosphate; sphingolipids; spectroscopy; enzymology; serine C-palmitoyltransferase
Abstract:
... Serine palmitoyltransferase, which is one of the α-oxamine synthase family enzymes, catalyzes the condensation reaction of L-serine and palmitoyl-CoA to form 3-ketodihydrosphingosine, the first and rate-determining step of the sphingolipid biosynthesis. As with other α-oxamine synthase family enzymes, the catalytic reaction is composed of multiple elementary steps, and the mechanism to control the ...
DOI:
10.1016/j.bbapap.2011.02.005

8. Metabolomic approaches reveal that cell wall modifications play a major role in ethylene‐mediated resistance against Botrytis cinerea

Author:
Amanda J. Lloyd; J. William Allwood; Catherine L. Winder; Warwick B. Dunn; James K. Heald; Simona M. Cristescu; Anushen Sivakumaran; Frans J. M. Harren; Joseph Mulema; Katherine Denby; Royston Goodacre; Aileen R. Smith; Luis A. J. Mur
Source:
plant journal 2011 v.67 no.5 pp. 852-868
ISSN:
0960-7412
Subject:
Arabidopsis; Botrytis cinerea; biochemical pathways; biological properties and phenomena; biosynthesis; cell walls; discriminant analysis; ethylene; fungi; genotype; metabolites; mutants; spectroscopy
Abstract:
... In Arabidopsis, resistance to the necrotrophic fungus Botrytis cinerea is conferred by ethylene via poorly understood mechanisms. Metabolomic approaches compared the responses of the wild‐type, the ethylene‐insensitive mutant etr1‐1, which showed increased susceptibility, and the constitutively active ethylene mutants ctr1‐1 and eto2 both exhibited decreased susceptibility to B. cinerea. Fourier t ...
DOI:
10.1111/j.1365-313X.2011.04639.x
PubMed:
21575089

9. Model membrane approaches to determine the role of calcium for the antimicrobial activity of friulimicin

Author:
Katrin Reder-Christ; Hildegard Falkenstein-Paul; Gabriela Klocek; Saad Al-Kaddah; Udo Bakowsky; Gerd Bendas
Source:
International journal of antimicrobial agents 2011 v.37 no.3 pp. 256-260
ISSN:
0924-8579
Subject:
Gram-positive bacteria; antibacterial properties; antibiotics; atomic force microscopy; binding capacity; biosynthesis; calcium; cell walls; lipopeptides; mechanism of action; salts; spectroscopy
Abstract:
... Friulimicin is a cyclic lipopeptide antibiotic, currently in clinical development, that possesses excellent activity against Gram-positive bacteria, including multiresistant strains. A recent study on the mode of action of friulimicin reported on the interference with bacterial cell wall biosynthesis via a calcium-dependent complexing of the bactoprenol phosphate carrier C₅₅-P. The calcium depende ...
DOI:
10.1016/j.ijantimicag.2010.11.024

10. Nanostructure of cellulose microfibrils in spruce wood

Author:
Anwesha N. Fernandes; Lynne H. Thomas; Clemens M. Altaner; Philip Callow; V. Trevor Forsyth; David C. Apperley; Craig J. Kennedy; Michael C. Jarvis
Source:
Proceedings of the National Academy of Sciences of the United States of America 2011 v.108 no.47 pp. E1195
ISSN:
0027-8424
Subject:
X-radiation; biomass; biosynthesis; cellulose; energy; engineering; hydrogen bonding; hydrophobicity; models; nanomaterials; spectroscopy; wood
Abstract:
... The structure of cellulose microfibrils in wood is not known in detail, despite the abundance of cellulose in woody biomass and its importance for biology, energy, and engineering. The structure of the microfibrils of spruce wood cellulose was investigated using a range of spectroscopic methods coupled to small-angle neutron and wide-angle X-ray scattering. The scattering data were consistent with ...
DOI:
10.1073/pnas.1108942108
PubMed:
22065760
PubMed Central:
PMC3223458

11. Phenolic Composition of Malbec Grape Skins and Seeds from Valle de Uco (Mendoza, Argentina) during Ripening. Effect of Cluster Thinning

Author:
Fanzone, Martin; Zamora, Fernando; Jofre, Viviana; Assof, Mariela; Pena-Neira, Alvaro
Source:
Journal of agricultural and food chemistry 2011 v.59 no.11 pp. 6120-6136
ISSN:
0021-8561
Subject:
Vitis vinifera; anthocyanins; biosynthesis; chemical composition; flavonols; flowering; grapes; phenolic compounds; ripening; seeds; spectroscopy; vineyards; wines; yield components; Argentina
Abstract:
... The phenolic composition of Malbec (Vitis vinifera L.) grape skins and seeds during ripening and the effect of cluster thinning (CT) in two consecutive seasons (2008–2009) were evaluated by high-performance liquid chromatography–diode array detection/electrospray ionization–mass spectrometry (HPLC-DAD/ESI-MS). Removal of 50% of clusters was performed at 40 days (T1), 80 days (T2), and 100 days aft ...
DOI:
10.1021/jf200073k
PubMed:
21520971

12. Use of the VvMybA1 gene for non-destructive quantification of promoter activity via color histogram analysis in grapevine (Vitis vinifera) and tobacco

Author:
Zhijian T. Li; Sadanand A. Dhekney; Dennis J. Gray
Source:
Transgenic research 2011 v.20 no.5 pp. 1087-1097
ISSN:
0962-8819
Subject:
Vitis vinifera; absorbance; anthocyanins; biosynthesis; color; fluorometry; genes; somatic embryos; spectroscopy; tobacco; transcription (genetics)
Abstract:
... We report the development of a convenient plant-based reporter system to analyze promoters and facilitate selection of genetically engineered plants. The VvMybA1 gene of grapevine (Vitis vinifera L.) regulates the last metabolic step of anthocyanin biosynthesis and its ectopic expression leads to anthocyanin production in otherwise non-pigmented cells. To develop an anthocyanin-based quantitative ...
DOI:
10.1007/s11248-010-9482-6
PubMed:
21229312

13. The stereochemistry of chlorophyll-c₃ from the haptophyte Emiliania huxleyi: The (13²R)-enantiomers of chlorophylls-c are exclusively selected as the photosynthetically active pigments in chromophyte algae

Author:
Tadashi Mizoguchi; Yuki Kimura; Taichi Yoshitomi; Hitoshi Tamiaki
Source:
Biochimica et biophysica acta 2011 v.1807 no.11 pp. 1467-1473
ISSN:
0005-2728
Subject:
Bacillariophyceae; Emiliania huxleyi; ambient temperature; autotrophs; biosynthesis; carotenoids; chlorophyll; dehydrogenation; enantiomers; high performance liquid chromatography; molecular models; natural selection; phylogeny; pigments; prokaryotic cells; spectroscopy; stereochemistry
Abstract:
... Chlorophyll(Chl)-c pigments in algae, diatoms and some prokaryotes are characterized by the fully conjugated porphyrin π-system as well as the acrylate residue at the 17-position. The precise structural characterization of Chl-c₃ from the haptophyte Emiliania huxleyi was performed. The conformations of the π-conjugated peripheral substituents, the 3-/8-vinyl, 7-methoxycarbonyl and 17-acrylate moie ...
DOI:
10.1016/j.bbabio.2011.07.008