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1. Reductive evolution of the mitochondrial processing peptidases of the unicellular parasites trichomonas vaginalis and giardia intestinalis.

Author

Ondrej Smíd, Anna Matusková, Simon R Harris, Tomás Kucera, Marián Novotný, Lenka Horváthová, Ivan Hrdý, Eva Kutejová, Robert P Hirt, T Martin Embley, Jirí Janata, and Jan Tachezy

Subjects
Immunologic diseases. Allergy, RC581-607, Biology (General), QH301-705.5
Abstract

Mitochondrial processing peptidases are heterodimeric enzymes (alpha/betaMPP) that play an essential role in mitochondrial biogenesis by recognizing and cleaving the targeting presequences of nuclear-encoded mitochondrial proteins. The two subunits are paralogues that probably evolved by duplication of a gene for a monomeric metallopeptidase from the endosymbiotic ancestor of mitochondria. Here, we characterize the MPP-like proteins from two important human parasites that contain highly reduced versions of mitochondria, the mitosomes of Giardia intestinalis and the hydrogenosomes of Trichomonas vaginalis. Our biochemical characterization of recombinant proteins showed that, contrary to a recent report, the Trichomonas processing peptidase functions efficiently as an alpha/beta heterodimer. By contrast, and so far uniquely among eukaryotes, the Giardia processing peptidase functions as a monomer comprising a single betaMPP-like catalytic subunit. The structure and surface charge distribution of the Giardia processing peptidase predicted from a 3-D protein model appear to have co-evolved with the properties of Giardia mitosomal targeting sequences, which, unlike classic mitochondrial targeting signals, are typically short and impoverished in positively charged residues. The majority of hydrogenosomal presequences resemble those of mitosomes, but longer, positively charged mitochondrial-type presequences were also identified, consistent with the retention of the Trichomonas alphaMPP-like subunit. Our computational and experimental/functional analyses reveal that the divergent processing peptidases of Giardia mitosomes and Trichomonas hydrogenosomes evolved from the same ancestral heterodimeric alpha/betaMPP metallopeptidase as did the classic mitochondrial enzyme. The unique monomeric structure of the Giardia enzyme, and the co-evolving properties of the Giardia enzyme and substrate, provide a compelling example of the power of reductive evolution to shape parasite biology.

Published
2008
Full Text
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2. Principles of Chemical Sensors

Author

Jiri Janata and Jiri Janata

Subjects
Chemical detectors
Abstract

viii The danger is that the result so obtained may be an experimental artifact. Another approach is to examine in as much detail as possible the principles underlying the operation of a new device. This may not lead to a new sensor immediately, but those developed along these lines tend to be more reliable. The accent in this book is therefore on the principles behind the operation ('the trade') rather than on a description of applications ('the tricks of the trade') of individual sensors. In this respect it is written for students at both graduate and upper undergraduate levels. Approximately one semester's worth of material is presented. The book may also be useful for scientists and engineers involved in the development of new types of chemical sensors or for those who discover that'somebody else's sensor just does not work as it should'and wish to know why. The book is divided into five sections dealing with the four principal modes of transduction: thermal, mass, electrochemical, and optical, as well as a general introduction common to the four types. I have included five appendixes, which are intended as a quick reference for readers who may not possess sufficient background in some areas covered in the main text. I have run out of symbols in both the Latin and Greek alphabets. In order to avoid confusion and ambiguity I have confined the use of a set of symbols to each chapter and provided glossaries at the end of each chapter.

Published
2013

3. High-throughput quantification of lincomycin traces in fermentation broth of genetically modified Streptomyces spp. Comparison of ultra-performance liquid chromatography and high-performance liquid chromatography with UV detection

Author

Jana, Olsovská, Markéta, Jelínková, Petr, Man, Markéta, Koberská, Jirí, Janata, and Miroslav, Flieger

Subjects
Organisms, Genetically Modified, Fermentation, Spectrophotometry, Ultraviolet, Sensitivity and Specificity, Chromatography, High Pressure Liquid, Streptomyces, Chromatography, Liquid, Lincomycin
Abstract

A new separation and quantification method using ultra-performance liquid chromatography (UPLC) with UV detection was developed for detection of lincomycin traces in fermentation broth of different Streptomyces spp. A similar high-performance liquid chromatography (HPLC) protocol was simultaneously developed for comparison purposes. Both methods were validated and showed a linear range of detector response for quantification of lincomycin in concentration from 3.125 to 1000.0 microgml(-1) with correlation coefficient 0.999 and recoveries ranging from 81.5 to 89.85% with precisionor =5%. Compared with the HPLC, the UPLC method offered high sample throughput and about 10 times lower consumption of solvents. The developed assays were used for determination of lincomycin production in genetically manipulated production strain Streptomyces lincolnensis and for determination of lincomycin production after heterologous expression of lincomycin biosynthetic gene cluster in non-producing strain Streptomyces coelicolor.

Published
2006

4. l-3,4-Dihydroxyphenyl alanine-extradiol cleavage is followed by intramolecular cyclization in lincomycin biosynthesis

Author

Jitka, Novotná, Ales, Honzátko, Petr, Bednár, Jan, Kopecký, Jirí, Janata, and Jaroslav, Spízek

Subjects
Estradiol, Molecular Structure, Cyclization, Two-Hybrid System Techniques, Escherichia coli, Electrophoresis, Capillary, Chromatography, Ion Exchange, Mass Spectrometry, Streptomyces, Dihydroxyphenylalanine, Lincomycin
Abstract

The LmbB1 protein, participating in the biosynthesis of lincomycin, was heterologously expressed in Escherichia coli, purified in its active form, and characterized as a dimer of identical subunits. Methods for purification and analysis of the LmbB1 reaction product were developed. Molecular mass and fragmentation pattern of the product revealed by capillary electrophoresis-mass spectrometry were in agreement with its proposed structure, 4-(3-carboxy-3-oxo-propenyl)-2,3-dihydro-1H-pyrrole-2-carboxylic acid. The LmbB1 is therefore a dioxygenase catalysing the 2,3-extradiol cleavage of the l-3,4-dihydroxyphenyl alanine aromatic ring. The final LmbB1 reaction product, a unique compound found in biosynthesis of lincomycin and expected in anthramycins, arises through subsequent cyclization of the primary cleavage product, 2,3-secodopa. A possible role of LmbB1 in 2,3-secodopa cyclization and alternative ways of the cyclization in the formation of biosynthetically related compounds, muscaflavin and stizolobinic acid, are discussed.

Published
2004

5. Principles of Chemical Sensors

Author

Jiri Janata and Jiri Janata

Subjects
Analytical chemistry, Electrochemistry, Physics, Astronomy, Materials science
Abstract

Do not learn the tricks of the trade, learn the trade I started teachinggraduate coursesin chemical sensors in early 1980s,?rst as a o- quarter (30 h) class then as a semester course and also as several intensive, 4–5-day courses. Later I organized my lecture notes into the?rst edition of this book, which was published by Plenum in 1989 under the title Principles of Chemical Sensors. I started working on the second edition in 2006. The new edition of Principles of Chemical Sensors is a teaching book, not a textbook. Let me explain the difference. Textbooks usually cover some more or less narrow subject in maximum depth. Such an approach is not possible here. The subject of chemical sensors is much too broad, spanning many aspects of physical and analytical chemistry, biochemistry, materials science, solid-state physics, optics, device fabrication, electrical engine- ing, statistical analysis, and so on. The challengefor me has been to present uniform logical coverage of such a large area. In spite of its relatively shallow depth, it is intended as a graduate course. At its present state the amount of material is more thancan be coveredin a one-semestercourse (45h). Two one-quartercourseswould be more appropriate. Because of the breadth of the material, the sensor course has a somewhat unexpected but, it is hoped, bene?cial effect.

Published
2009

6. Combined Gas Microflowmeter and Potentiometric Sensor

Author

Domanský, Karel and Jirí Janata, Jirí Janata

Abstract

A gas microflowmeter based on a potentiometric chemical sensor is demonstrated. The flowmeter operates on the hot-wire principle. Electric current is passed through a platinum microbridge. A preset bridge resistance is kept constant by regulating the heating current. By measuring the changes in the heating current, the calibration flow curve can be obtained. The temperature profiles of both the electrically heated microbridge and the substrate in its vicinity, measured with an infrared microscope, are presented.

Published
1995
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7. Chemical Sensors and Microinstrumentation

Author

ROYCE W. MURRAY, RAYMOND E. DESSY, WILLIAM R. HEINEMAN, JIRI JANATA, W. RUDOLF SEITZ, M. E. Meyerhoff, D. M. Pranitis, H. S. Yim, N. A. Chaniotakis, S. B. Park, George B. Sigal, Dean G. Hafeman, J. Wallace Parce, Harden M. McConnell, Robert J. Geise, Alexander M. Yacynych, Louis A. Coury, Christos Galiatsatos, Edward W. Huber, Sandra Sponaugle, Yoshihito Ikariyama, Naoki Shimada, Shigeru Yamauchi, H. Allen O. Hill, Napthali P. Klein, A. Surya N. Murthy, Ioanna S. M. Psalti, R. Mark Wightman, Leslie J. May, John Baur, David Leszczyszyn, Eric Kristensen, Masuo Aizawa, Masaru Tanaka, Lloyd Burgess, Larry Arney, James Petersen, Hank Wohltjen, David S. Ballantine, N. L. Jarvis, Edward T. Zellers, A. J. Ricco, S. J. Martin, T. M. Niemczyk, G. C. Frye, C. J. Brinker, Steven J. Lasky, Daniel A. Buttry, David R. Walt, Christiane Munkholm, Ping Yuan, Shufang Luo, Steven Barnard, Ma Wangbai, Zhang Zhujun, Scott M. Stole, Thomas P. Jones, Lai-Kwan Chau, Marc D. Porter, Mark A. Arnold, Michael J. Sepaniak, Bruce J. Tromberg, Jean-Pierre Alarie, James R. Bowyer, ROYCE W. MURRAY, RAYMOND E. DESSY, WILLIAM R. HEINEMAN, JIRI JANATA, W. RUDOLF SEITZ, M. E. Meyerhoff, D. M. Pranitis, H. S. Yim, N. A. Chaniotakis, S. B. Park, George B. Sigal, Dean G. Hafeman, J. Wallace Parce, Harden M. McConnell, Robert J. Geise, Alexander M. Yacynych, Louis A. Coury, Christos Galiatsatos, Edward W. Huber, Sandra Sponaugle, Yoshihito Ikariyama, Naoki Shimada, Shigeru Yamauchi, H. Allen O. Hill, Napthali P. Klein, A. Surya N. Murthy, Ioanna S. M. Psalti, R. Mark Wightman, Leslie J. May, John Baur, David Leszczyszyn, Eric Kristensen, Masuo Aizawa, Masaru Tanaka, Lloyd Burgess, Larry Arney, James Petersen, Hank Wohltjen, David S. Ballantine, N. L. Jarvis, Edward T. Zellers, A. J. Ricco, S. J. Martin, T. M. Niemczyk, G. C. Frye, C. J. Brinker, Steven J. Lasky, Daniel A. Buttry, David R. Walt, Christiane Munkholm, Ping Yuan, Shufang Luo, Steven Barnard, Ma Wangbai, Zhang Zhujun, Scott M. Stole, Thomas P. Jones, Lai-Kwan Chau, Marc D. Porter, Mark A. Arnold, Michael J. Sepaniak, Bruce J. Tromberg, Jean-Pierre Alarie, and James R. Bowyer

Subjects
Chemical detectors--Congresses, Engineering instruments--Congresses
Published
1989

8. Solid State Chemical Sensors

Author

Jiri Janata and Jiri Janata

Subjects
Chemical detectors, Solid state chemistry
Abstract

Solid State Chemical Sensors reviews the basic chemical and physical principles involved in the construction and operation of solid state sensors. A major portion of the book is devoted to explanation of the basic mechanism of operation and the many actual and potential applications of field effect transistors for gas and solution sensing. This text is comprised of four chapters; the first of which describes the basics of device fabrication. Emphasis is placed on the physical description of semiconductor devices with catalytic metal gates, along with their drawbacks and their promise. The behavior of hydrogen in the Pd-SiO2 system is also considered, and some applications of hydrogen-sensitive transistors, such as smoke detection and biochemical reaction monitoring, are described. The second chapter focuses on chemically sensitive field effect transistors and their thermodynamics, while the third chapter explains the general fabrication procedure for solid state chemical sensors. The final chapter introduces the reader to piezoelectric and pyroelectric chemical sensors, paying particular attention to the sensor nature of piezoelectricity, the piezoelectric gravimetric sensor, and pyroelectric gas analysis. This book is intended to assist electrical engineers in understanding the chemistry involved in the construction and operation of solid state sensors and to educate chemists in solid state science.

Published
1985

9. Interfacial Design and Chemical Sensing

Author

THOMAS E. MALLOUK, D. JED HARRISON, T. Bein, Y. Yan, Mark E. Davis, Gordon G. Cross, Thomas M. Fyles, Pedro J. Montoya-Pelaez, Wilma F. van Straaten-Nijenhuis, Xin Zhou, Houston Byrd, John K. Pike, Margaret L. Showalter, Scott Whipps, Daniel R. Talham, Louis C. Brousseau, Katsunori Aoki, Huey C. Yang, Rick Cox, Dario Gomez, Daniel A. Buttry, Peter Bonnesen, Kenneth N. Raymond, Andrew B. Bocarsly, Jonathan K. M. Chun, Michael T. Kelly, J. T. McDevitt, D. C. Jurbergs, S. G. Haupt, Richard M. Crooks, Orawon Chailapakul, Claudia B. Ross, Li Sun, Jonathan K. Schoer, Kazunori Odashima, Masao Sugawara, Yoshio Umezawa, Marcin Majda, Naotoshi Nakashima, Toshiyuki Taguchi, Michael Thompson, M. Donata Frank, David C. Stone, David J. Dunaway, Robin L. McCarley, Jiri Janata, Cynthia Bruckner-Lea, John Conroy, Andras Pungor, Karin Caldwell, Phillip W. Carter, Lynn M. Frostman, Andrew C. Hillier, Michael D. Ward, C. D. England, G. E. Collins, T. J. Schuerlein, N. R. Armstrong, M. Pomerantz, R. J. Purtell, R. J. Twieg, S.-F. Chuang, W. Reuter, B. N. Eldridge, F. P, THOMAS E. MALLOUK, D. JED HARRISON, T. Bein, Y. Yan, Mark E. Davis, Gordon G. Cross, Thomas M. Fyles, Pedro J. Montoya-Pelaez, Wilma F. van Straaten-Nijenhuis, Xin Zhou, Houston Byrd, John K. Pike, Margaret L. Showalter, Scott Whipps, Daniel R. Talham, Louis C. Brousseau, Katsunori Aoki, Huey C. Yang, Rick Cox, Dario Gomez, Daniel A. Buttry, Peter Bonnesen, Kenneth N. Raymond, Andrew B. Bocarsly, Jonathan K. M. Chun, Michael T. Kelly, J. T. McDevitt, D. C. Jurbergs, S. G. Haupt, Richard M. Crooks, Orawon Chailapakul, Claudia B. Ross, Li Sun, Jonathan K. Schoer, Kazunori Odashima, Masao Sugawara, Yoshio Umezawa, Marcin Majda, Naotoshi Nakashima, Toshiyuki Taguchi, Michael Thompson, M. Donata Frank, David C. Stone, David J. Dunaway, Robin L. McCarley, Jiri Janata, Cynthia Bruckner-Lea, John Conroy, Andras Pungor, Karin Caldwell, Phillip W. Carter, Lynn M. Frostman, Andrew C. Hillier, Michael D. Ward, C. D. England, G. E. Collins, T. J. Schuerlein, N. R. Armstrong, M. Pomerantz, R. J. Purtell, R. J. Twieg, S.-F. Chuang, W. Reuter, B. N. Eldridge, and F. P

Subjects
Separation (Technology)--Congresses, Chemical detectors--Congresses
Published
1994

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