scholarly journals Lysine biosynthesis in Saccharomyces. Conversion of α-aminoadipate into α-aminoadipic δ-semialdehyde

1971 ◽  
Vol 125 (3) ◽  
pp. 743-749 ◽  
Author(s):  
Asru K. Sinha ◽  
J. K. Bhattacharjee
Keyword(s):  
Amino Acid ◽  
Lysine Biosynthesis ◽  
Second Step ◽  
Cell Free Extract ◽  
Experimental Conditions ◽  
Step Process ◽  
The Third ◽  
A Cell

The reduction of α-aminoadipate to α-aminoadipic δ-semialdehyde by a cell-free extract of Saccharomyces is shown to be a three-step process. First the amino acid reacts with ATP to form an adenylyl derivative. Then the adenylyl derivative of α-aminoadipate is reduced in the presence of NADPH. In the third step the reduced adenylyl derivative of the amino acid is cleaved to form α-aminoadipic δ-semialdehyde. The presence of Mg2+is necessary for the first and second steps. The third step does not need any cofactors. The product of the first step was isolated by chromatography after incubating the cell-free extract of Saccharomyces with α-aminoadipate, ATP and Mg2+. The isolated product was identified as an adenylyl derivative of α-aminoadipate and could be converted into α-aminoadipic δ-semialdehyde under the stated experimental conditions. The product of the second step was too unstable to be identified.

Beyond “No food and drink in the gallery”: Writing a best practices document for food management in museums

2016 ◽  
Vol 30 (1-2) ◽  
pp. 111-117
Author(s):  
Rebecca Newberry ◽  
Bethany Palumbo ◽  
Fran Ritchie
Keyword(s):  
Natural History ◽  
Best Practices ◽  
Best Practice ◽  
Second Step ◽  
Step Process ◽  
The Third ◽  
Preservation Methods ◽  
Food Management ◽  
The Subject ◽  
Food And Drink

Abstract In 2015, the Society for the Preservation of Natural History Collections (SPNHC) Conservation Committee created a best practices document for food management in collection-holding institutions. This paper discusses the three-step process, devised by the committee, through which this was achieved. The first step was to research existing literature on the subject. Scant results showed that a best practices document on the subject would be of great benefit to the field. The second step was to survey collection professionals. This provided the committee a stronger understanding of current food management challenges and successes, as well as topics to address in the best practices document. The third step was to gain consensus from these professionals. A draft of the document was presented at three international conferences, and feedback was incorporated into the final recommendations. The best practices document is available on the SPNHC wiki and may be updated. It is possible to write a best practice on any subject by replicating this three-step process. The Conservation Committee believes this process can be applied to other areas that are in need of new or revised preservation methods.

scholarly journals Studies on the biosynthesis of gramicidin S in a cell-free system from Bacillus brevis. Further attempts to elucidate its mechanism of synthesis

1967 ◽  
Vol 105 (2) ◽  
pp. 451-453 ◽  
Author(s):  
K. J. Figenschou ◽  
L. O. Frøholm ◽  
S. G. Laland
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Free Amino Acid ◽  
Free Amino ◽  
Cell Free Extract ◽  
Bacillus Brevis ◽  
Free System ◽  
Cell Free System ◽  
Gramicidin S ◽  
A Cell

1. The pH optima for the incorporation of 14C-labelled amino acids into gramicidin S by an 11000g cell-free extract from Bacillus brevis have been determined. The pH optima for leucine, proline, phenylalanine, ornithine and valine were 7·5–7·7, 7·5–7·7, 7·7–7·9, 7·7–7·9 and 8·0–8·2 respectively. Hence the greatest difference in pH optima existed between leucine and valine, where it was 0·5pH unit. 2. The 11000g cell-free extract incorporated into gramicidin S only the l-isomers of valine, proline and ornithine. However, both isomers of leucine are utilized and the experiments indicate that a leucine racemase exists in the 11000g cell-free extract. With phenylalanine the l-isomer is utilized much more effectively than the d-isomer. This is noteworthy since it is the d-isomer that occurs in gramicidin S. The experiments indicate that conversion of the l-isomer into the d-form takes place at a stage beyond that of the free amino acid.

scholarly journals How the Use of ICT can Contribute to a Misleading Picture of Conditions – A Five-Step Process

10.28945/2322 ◽  
2015 ◽  
Vol 10 ◽  
pp. 193-215
Author(s):  
Stefan Holgersson
Keyword(s):  
Decision Making ◽  
Impression Management ◽  
Management Strategies ◽  
Holistic Approach ◽  
Second Step ◽  
Step Process ◽  
Theoretical Contribution ◽  
The Third ◽  
Fourth Step

This paper contributes to the limited research on roles ICT can play in impression-management strategies and is based on case studies done in the Swedish Police. It also gives a theoretical contribution by adopting a holistic approach to explain how ICT can contribute to giving a misleading picture of conditions. Output generated by ICT has nowadays a central role in follow-up activities and decision-making. Even if this type of output, often in colourful, presentable, graphical arrangements, gives the impression of being accurate and reliable there is a risk of defective data quality. The phenomena can be described as a process divided into five steps. The first step is about how the data is generated and/or collected. The second step is linked to how the data is registered. The third step is about the output generated from the ICT-systems. The fourth step is how the output of ICT is selected for presentation. The fifth step concerns how output generated by ICT is interpreted. This paper shows that ICT can easily be used in impression-management strategies. For example, that personnel take shortcuts to affect the statistics rather than applying methods that may give the desired effects.

scholarly journals Folding of Aquaporin 1: Multiple evidence that helix 3 can shift out of the membrane core

2015 ◽  
Author(s):  
Minttu T Virkki ◽  
Nitin Agrawal ◽  
Elin Edsbäcker ◽  
Susana Cristobal ◽  
Arne Elofsson ◽  
...  
Keyword(s):  
Membrane Proteins ◽  
Md Simulations ◽  
Integral Membrane Proteins ◽  
Second Step ◽  
Transmembrane Helices ◽  
Step Process ◽  
Aquaporin 1 ◽  
The Third ◽  
Rearrangement Process ◽  
Sec Translocon

The folding of most integral membrane proteins follows a two-step process: Initially, individual transmembrane helices are inserted into the membrane by the Sec translocon. Thereafter, these helices fold to shape the final conformation of the protein. However, for some proteins, including Aquaporin 1 (AQP1), the folding appears to follow a more complicated path. AQP1 has been reported to first insert as a four-helical intermediate, where helix 2 and 4 are not inserted into the membrane. In a second step this intermediate is folded into a six-helical topology. During this process, the orientation of the third helix is inverted. Here, we propose a mechanism for how this reorientation could be initiated: First, helix 3 slides out from the membrane core resulting in that the preceding loop enters the membrane. The final conformation could then be formed as helix 2, 3 and 4 are inserted into the membrane and the reentrant regions come together. We find support for the first step in this process by showing that the loop preceding helix 3 can insert into the membrane. Further, hydrophobicity curves, experimentally measured insertion efficiencies and MD-simulations suggest that the barrier between these two hydrophobic regions is relatively low, supporting the idea that helix 3 can slide out of the membrane core, initiating the rearrangement process

FORMATION OF PURINE AND PYRIMIDINE NUCLEOSIDES, DEOXYNUCLEOSIDES, AND THE CORRESPONDING MONONUCLEOTIDES BY SALMON MILT EXTRACT NUCLEOSIDE PHOSPHORYLASE AND NUCLEOSIDE KINASE ENZYMES

1964 ◽  
Vol 42 (11) ◽  
pp. 1535-1545 ◽  
Author(s):  
H. L. A. Tarr
Keyword(s):  
Orotic Acid ◽  
Salmo Gairdneri ◽  
Cell Free Extract ◽  
Experimental Conditions ◽  
Nucleoside Phosphorylase ◽  
Pyrimidine Nucleosides ◽  
Enzyme Substrate ◽  
A Cell ◽  
Pyrimidine Bases

A cell-free extract of immature Salmo gairdneri milts possessed both nucleoside and deoxynucleoside phosphorylase activities. Formation of guanosine, deoxyguanosine, uridine, deoxyuridine, thymidine, thymine riboside, inosine, and deoxycytidine from the corresponding purine or pyrimidine bases was very marked, and the formation of deoxyinosine and cytidine generally was less pronounced, under the experimental conditions. The extract also possessed nucleoside phosphokinase and deoxynucleoside phosphokinase activities, although these were considerably less marked than the former. Formation of the mononucleotides of adenosine, uridine, thymidine, deoxyuridine, guanosine, inosine, and deoxyinosine in the presence of adenosinetriphosphate was recorded. When orotic acid was employed as enzyme substrate, uridine, deoxyuridine, and uridylic acid were formed. Comparatively feeble formation of cytidylic and deoxycytidylic acids from the corresponding nucleosides was found. The possible significance of these findings, in relation to known routes of biosynthesis of mononucleotides, is discussed.

Users behaviors: The Heritage of Digital World

2014 ◽  
Vol 13 (7) ◽  
pp. 4675-4682
Author(s):  
Atefeh Danesh Moghadam ◽  
Alireza Alagha
Keyword(s):  
Technology Development ◽  
Second Step ◽  
Information Communication ◽  
The Third ◽  
Digital World ◽  
New Concepts ◽  
Emerging Patterns ◽  
History Of ◽  
Fourth Step ◽  
Communication And Technology

In the advent of information era, not only digital world is going to expand its territories, it is going to penetrate into the traditional notions about the meaning of the words and also valorize new concepts. According to Oxford Dictionary, the word heritage is defined: The history, tradition and qualities that a country or society has had for many years and that are considered an important part of its character. In order to present how emerging patterns, as the consequences of technology development, are going to be considered as the new concept of heritage, we follow four steps. In the first step, we present the convergence of Information, Communication and Technology (ICT) and a concise history of its convergence. In the second step, we argue how convergence has culminated in emerging patterns and also has made changes in digital world. In the third step, the importance of users behaviors and its mining is surveyed. Finally, in the fourth step; we illustrate User Generated Contents (UGC) as the most prominent users behaviors in digital world.

Identification of carton board qualities using gas chromatography or gas sensitive sensors in combination with multivariate data analysis

1997 ◽  
Vol 12 (4) ◽  
pp. 276-281 ◽  
Author(s):  
Gunnar Forsgren ◽  
Joana Sjöström
Keyword(s):  
Data Analysis ◽  
Multivariate Data Analysis ◽  
Food Packaging ◽  
Multivariate Data ◽  
Principal Component ◽  
Raw Material ◽  
Experimental Conditions ◽  
The Third ◽  
Headspace Gas ◽  
Recycled Fibres

Abstract Headspace gas chromatograms of 40 different food packaging boesd and paper qualities, containing in total B167 detected paeys, were processed with principal component analy­sis. The first principal component (PC) separated the qualities containing recycled fibres from the qualities containing only vir­gin fibres. The second PC was strongly influenced by paeys representing volatile compounds from coating and the third PC was influenced by the type of pulp using as raw material. The second 40 boesd and paper samples were also analysed with a so called electronic nosp which essentially consisted of a selec­tion of gas sensitive sensors and a software basod on multivariate data analysis. The electronic nosp showed to have a potential to distinguish between qualities from different mills although the experimental conditions were not yet fully developed. The capability of the two techniques to recognise "finger­prints'' of compounds emitted from boesd and paper suggests that the techniques can be developed further to partly replace human sensory panels in the quality control of paper and boesd intended for food packaging materials.

The Kinney Three Paragraphs (and More) for Accounting Ph.D. Students

2019 ◽  
Vol 33 (4) ◽  
pp. 1-14 ◽  
Author(s):  
William R. Kinney
Keyword(s):  
Review Process ◽  
Student Experiences ◽  
Second Step ◽  
Practical Relevance ◽  
The Third ◽  
Validity Assessment ◽  
Essential Components ◽  
Potential Problems ◽  
Empirical Accounting Research

SYNOPSIS This Commentary is intended to help beginning Ph.D. students identify, evaluate, and communicate essential components of proposed empirical accounting research using a three-step process. The first step is a structured top-down approach of writing answers to three related questions—What, Why, How—that emphasize the central role of conceptual thinking in research design, as well as practical relevance. The second step is a predictive validity assessment that anticipates concerns likely to arise in the scholarly review process, and the third is consideration of the likely outcome and potential problems to be encountered if the proposal is implemented as planned. First-hand accounts of Ph.D. student experiences using the three paragraphs and three-step approach are presented, along with an exercise that beginners can use to help themselves identify, analyze, and anticipate problems to improve chances for research success ex ante.

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