Effect of tea catechins on tRNA structure and dynamics

Abbreviations C catechin

ECG epicatechin gallate

EGCG Epigallocatechin gallate

A Adenine

C cytosine

G Guanine

U uracil

FTIR Fourier transform infrared

Communicated by Ramaswamy H. Sarma     

An Approach to the Development of Field Studies in Urban Areas

Integrated Science—The Wreake Valley Project D. TINBERGEN and P. THORBURN (Eds) Book 1, 120 pp., illustrated. £1.50. Book 2, 104 pp., illustrated. £1.75. Book 3, 136 pp., illustrated. £2.25. London: Edward Arnold, 1976. Reviewed by John May

Stirling Educational Monographs No. 1. Attitude Goals in Secondary School Science S. BROWN 77 pp. University of Stirling. 1976. £1.75. Reviewed by Clive Carré and Henry Crowther

No. 2. Innovations in Integrated Science in Scottish Secondary Schools S. BROWN, D. McINTYRE, E. DREVER and J. KERI DAVIES 89 pp. University of Stirling, 1976. £1.00. Reviewed by Tessa Carrick

Outline Studies in Biology 64 pp. each, illustrated. London: Chapman and Hall, 1976. £1.30 each. Biological Energy Conservation C. W. JONES Control of Enzyme Activity P. COHEN Metabolic Regulation R. M. DENTON and C. I. POGSON Reviewed by John H. Duffus

Population Genetics L. M. COOK Reviewed by T. J. Crawford

Cytogenetics of Man and other Animals A. McDERMOTT Reviewed by J. A. Beardmore

RNA Biosynthesis R. H. BURDON Protein Biosynthesis A. E. SMITH Reviewed by C. M. Bray

Basic Biology Course Books 3, 5, 8, and 9 London: Cambridge University Press, 1976.

Book 3 Dynamic Aspects of Cells M. A. TRIBE, I. TALLAN, M. R. ERAUT and R. K. SNOOK 119 pp., illustrated. £6.20 boards, £2.90 paper.

Book 5 Cell Membranes M. A. TRIBE, M. R. ERAUT and R. K. SNOOK 79 pp., illustrated. £5.00 boards, £2.50 paper. Super 8 mm film loop (Phagocytosis) £8.00.

Book 8 Metabolism and Mitochondria M. A. TRIBE, M. R. ERAUT and R. K. SNOOK 142 pp., illustrated. £8.00 boards, £3.50 paper. Filmstrip £3.50; cassette £3.80.

Book 9 Protein Synthesis M. A. TRIBE, I. TALLAN, M. R. ERAUT and R. K. SNOOK 103 pp., illustrated. £6.00 boards, £2.75 paper. Reviewed by Colin Stoneman

Population Cytogenetics Studies in Biology, No. 70 B.JOHN 76 pp., illustrated. London: Edward Arnold, 1976. £3.00 boards, £1.50 paper. Reviewed by J. A. Beardmore

Biology Colour Units Helpful and Harmful Organisms M. Sanderson Urban Ecology D. Gilman Co-ordination C. Morgan Movement D. Gray Each 24 pp, illustrated. London: Macdonald Educational, 1977. 75p each. Reviewed by John May

The Natural World : The Mitchell Beazley Joy of Knowledge Library J. MITCHELL (Ed.) 272 pp., illustrated. London: Mitchell Beazley, 1977. £12.50. Reviewed by P. J. Kelly

Human and Social Biology G. USHER 256 pp., illustrated. Plymouth, Devon: Macdonald and Evans, 1977. £1.95. Reviewed by A. Cornwell

Safeguards in the School Laboratory 28 pp., Hatfield, Herts: Association for Science Education, 1976. 35p. Reviewed by Tessa Carrick

A First Science Dictionary D. J. LUCAS, H. I. JAMES, and O. J. SIMPSON 208 pp. London: Edward Arnold, 1976. £1.95. Reviewed by John Feltwell

Introduction to Genetics Third Edition D. G. MACKEAN 42 pp., illustrated. London: John Murray, 1977. £1.40. Reviewed by Tessa Carrick

The Wash water storage feasibility study: a report on the ecological studies 36 pp., illustrated. London: Natural Environment Research Council. Publication series C No. 15, 1976. Free. Reviewed by John A. Barker

Higher Education Film Library Catalogue BRITISH UNIVERSITIES FILM COUNCIL London: BUFC, 1977. £1.00. Reviewed by John A. Barker

Biology: Principles and Issues WILLIAM C. SCHEFLER 370pp., illustrated. London: Addison-Wesley, 1976. £9.10. Reviewed by H. W. Grenville

Guide to Living Mammals J. E. WEBB, J. A. WALLWORK, and J. H. ELGOOD 152 pp., illustrated. London: Macmillan, 1977. £2.95. Reviewed by H. V. Wyatt

Applied Medical Microbiology J. G. COLLEE 121 pp., illustrated. Oxford: Blackwell Scientific, 1976. £2.80. Reviewed by G. E. Mathison

General Microbiology Fourth edition R. Y. STANIER, E. A. ADELBERG and J. L. INGRAHAM 871pp., illustrated. London: Macmillan, 1977. £15.00 boards, £7.95 paper. Reviewed by C. G. Gayford

Fundamentals of Mycology Second edition J. H. BURNETT 673 pp., illustrated. London: Edward Arnold, 1976. £27.50. Reviewed by B. W. Bainbridge

Metals and Metabolism D. A. PHIPPS 134 pp., London: Oxford University Press (Clarendon), 1976. £5.00 boards, £2.50 paper. Reviewed by C. M. Bray

Biochemical Systems Analysis M. A. SAVAGEAU 379 pp., illustrated. London: Addison-Wesley, 1976. £21.20 boards, £13.20 paper. Reviewed by J. H. Parish

The Biochemistry of the Tissues Second edition P. BANKS, W. BARTLEY, and L. M. BIRT 493 pp. Chichester, Sussex: John Wiley, 1976. £14.50 boards, £6.25 paper. Reviewed by John Feltwell

Genetics and Adaptation Studies in Biology, No. 69 E. B. FORD 58 pp., illustrated. London: Edward Arnold, 1976. £2.60 boards, £1.30 paper. Reviewed by R. A. E. Tilney-Bassett

The Comparative Endocrinology of the Invertebrates Second edition K. C. HIGHNAM and L. HILL 357 pp., illustrated. London: Edward Arnold, 1977. £16.00 boards, £8.50 paper. Reviewed by K. Simkiss

Muscles and Movement K. M. BACKHOUSE 48 pp., illustrated. London: Hart Davis, 1976. £1.75. Reviewed by Jackie Hardie

Herbicides: Physiology, Biochemistry, Ecology, Vol. 2 Second edition L. J. AUDUS (Ed.) 564 pp., illustrated. London: Academic Press, 1976. £17.50. Reviewed by Donald S. H. Drennan

Introduction to Ecology R. DAJOZ Translated by A. SOUTH 416 pp., Sevenoaks, Kent : Hodder and Stoughton, 1977. £7.50 boards, £4.45 paper. Reviewed by D. M. Keith-Lucas

Human Sex and Sexuality E. B. STEEN and J. H. PRICE 338 pp., illustrated. Chichester, Sussex: John Wiley, 1977. £7.00. Reviewed by Donald Reid

Rabies : The Facts C. KAPLAN (Ed.) 116 pp., illustrated. Oxford: Oxford University Press, 1977. £1.95 (Also published in paperback by Corgi Books, London. 75p.) Reviewed by W. C. Noble

Introduction to Environmental Remote Sensing E. C. BARRETT and L. F. CURTIS 336 pp., illustrated. London: Chapman and Hall, 1976. £11.00 boards, £5.95 paper. Reviewed by Monical M. Cole

Light and Life L. O. BJÖRN 249 pp., illustrated. London: Hodder and Stoughton, 1976. £3.45 boards, £1.75 paper. Reviewed by John Feltwell     

The Food Intake of Plants

Schank, Roger C. with Peter C. Childers The Cognitive Computer: On Language, Learning, and Artificial Intelligence Reading, Mass.: Addison-Wesley, 1984 268 pp. $17.95. Reviewed by Gerald R. Rising.

Brown, Vinson Building Your Own Nature Museum for Study and Pleasure, 2d ed. New York: Arco Pub., 1984 161 pp. $12.95 hardcover, $7.95 paper. Reviewed by A. Gilbert Wright.

Heppenheimer, T. A. The Man-Made Sun: The Quest for Fusion Power Boston, Mass.: Little, Brown and Co., 1984 347 pp., $19.95 hardcover. Reviewed by Laurence A. Marschall.

Stiebing, William H., Jr. Ancient Astronauts, Cosmic Collisions, and Other Popular Theories About Man's Past Buffalo, N.Y.: Prometheus Books, 1984 217 pp. $19.95 hardcover, $9.95 paper. Reviewed by Joseph S. Tenn.

Finucane, R. C. Appearances of the Dead: A Cultural History of Ghosts Buffalo, N.Y.: Prometheus Books, 1984 232 pp. $18.95 hardcover. Reviewed by Russell F. Trimble.

De Carlo, Nicola Alberto Psychological Games New York: Facts on File, 1984 184 pp. $22.95 hardcover, $12.95 paper. Reviewed by Barry Guinagh.     

Audio-Visual Approaches to Science Teaching

From Instinct to Intelligence/How Animals Learn by Gloria Kirshner. Grosset &; Dunlap Publishers, 51 Madison Ave., New York, N.Y. 10010. 1970. 127 pp., $3.95. Reviewed by Robert C. Hayden.

A Pictorial History of Oceanographic Submersibles by James B. Sweeney, Crown Publishers, Inc., 419 Park Ave. South, New York, N.Y. 10016. 1970. 314 pp., Indexed, Bibliography. $9.95. Reviewed by Robert C. Hayden.

Where the Winds Sleep: Man's Future on the Moon—A Projected History by Neil P. Ruzic. Doubleday &; Co., Inc., Garden City, New York, 1970. 236 pp., Indexed. $5.95. Reviewed by Robert C. Hayden.

Hunters and Collectors by George H. T. Kimble. McGraw-Hill Book Co., 330 West 42nd St., New York, N.Y. 10036. 1970. 48 pp., Indexed. $4.95 trade edn., $4.72 lib. edn. Reviewed by Robert C. Hayden.

Life in Ponds by Jean Gorvett. American Heritage Press, New York. 1920. 31 pp. Reviewed by Robert C. Hayden.

Discovering What Goldfish Do by Seymour Simon. McGraw-Hill Book Co., 330 West 42nd St., New York, N.Y. 1970. 47 pp. $3.95 trade edn. $3.83 lib. edn. Reviewed by Robert C. Hayden.

Building and Flying Scale Model Aircraft 3rd Edition by Walter A. Musciano. Herman Publishing Service, Division of Cahners Pub. Co., Inc., 221 Columbus Ave., Boston, Mass. 02116. 1970. 245 pp. Glossary, $7.95. Reviewed by Robert C. Hayden.     

Characterization of a Temperate Phage and Four Bacteriocins Produced by Nonpathogenic Clostridium Species

We previously reported the isolation of a temperate phage (named KT) and several bacteriocins (named clostocins) from strains of nonpathogenic Clostridium species. Later, the induction and some properties of the phage and four clostocins (A, B, C and D) were examined.

The phage was induced by UV light and mitomycin C. The phage had a polygonal head (about 85mμ in diameter) and a tail with contractile sheath (about 100mμ in length). Some other properties of the phage were also studied; plaque morphology, stability in salt solution, inactivation by UV light, pH stability, thermal inactivation, host-range and lysis of infected culture.

Clostocins A and D were partially induced by UV light and mitomycin C, whereas that of B and C were not. All clostocins failed to pass through a dialysis membrane, and were insensitive to UV light and to ribo- and deoxyribonuclease. They were destroyed by some proteolytic enzymes, but differences in degree of their susceptibility were observed among them. Clostocins A and D were very thermo-stable, whereas B and C were relatively thermo-labile. Clostocins A and D acted on some strains in the genus Clostridium, whereas B and C did on many strains in the family Bacillaceae.

There was no demonstrable serological relationship between phage KT and clostocin A, although they seemed to adsorb on the same bacterial receptor.     

Development of functionalised polyelectrolyte capsules using filamentous Escherichia coli cells

Background

Chloronitrophenols (CNPs) are widely used in the synthesis of dyes, drugs and pesticides, and constitute a major group of environmental pollutants. 4-Chloro-2-nitrophenol (4C2NP) is an isomer of CNPs that has been detected in various industrial effluents. A number of physicochemical methods have been used for treatment of wastewater containing 4C2NP. These methods are not as effective as microbial degradation, however.

Results

A 4C2NP-degrading bacterium, Exiguobacterium sp. PMA, which uses 4C2NP as the sole carbon and energy source was isolated from a chemically-contaminated site in India. Exiguobacterium sp. PMA degraded 4C2NP with the release of stoichiometeric amounts of chloride and ammonium ions. The effects of different substrate concentrations and various inoculum sizes on degradation of 4C2NP were investigated. Exiguobacterium sp. PMA degraded 4C2NP up to a concentration of 0.6 mM. High performance liquid chromatography and gas chromatography–mass spectrometry identified 4-chloro-2-aminophenol (4C2AP) and 2-aminophenol (2AP) as possible metabolites of the 4C2NP degradation pathway. The crude extract of 4C2NP-induced PMA cells contained enzymatic activity for 4C2NP reductase and 4C2AP dehalogenase, suggesting the involvement of these enzymes in the degradation of 4C2NP. Microcosm studies using sterile and non-sterile soils spiked with 4C2NP were carried out to monitor the bioremediation potential of Exiguobacterium sp. PMA. The bioremediation of 4C2NP by Exiguobacterium sp. PMA was faster in non-sterilized soil than sterilized soil.

Conclusions

Our studies indicate that Exiguobacterium sp. PMA may be useful for the bioremediation of 4C2NP-contaminated sites. This is the first report of (i) the formation of 2AP in the 4C2NP degradation pathway by any bacterium and (iii) the bioremediation of 4C2NP by any bacterium.

     

Book Reviews

Psychobiology: The Biological Bases of Behavior Pp. 382, illustrated. New York: Scientific American, 1967. 70s. (cloth), 40s. (paper). Reviewed by O. Lowenstein

Organisation in Plants W. M. M. BARON Pp. vi+218, 117 figs. London: Edward Arnold Ltd., 2nd ed., 1967.18s. (paper), 30s. (boards). Reviewed by J. W. Hannay

A First Biology ERIC SPRINGTHORPE Pp. 103. London: Longmans, Green & Co. Ltd., 1967. 10s. 6d. Reviewed by J. A. Barker

The Biology of Lichens MASON E. HALE, JR. Pp. viii + 176, 60 figs, 15 plates. London: Edward Arnold Ltd., 1967. 42s. Reviewed by K. A. Kershaw

Experiments in the Study of Biology J. J. W. BAKER, G. E. ALLEN, E. GAGE and S. K. WEBSTER Pp. 58. London: Addison-Wesley, 1967. Reviewed by C. F. Stoneman

Microbiological Methods C. H. COLLINS Pp. xii+404, illustrated. London: Butterworths, 2nd ed. 1967. 62s. Reviewed by N. J. Butler

The New Microbiology Ed. JOHN E. FLYNN New York: McGraw Hill Book Co., 1966. Reviewed by W. Howard Hughes

,i>Pergamon Programmed Texts Introduction to Genetics: Science of Heredity A. J. S. MCMILLAN Pp. 410, 64 figs, 6 plates. 1966. J. Audrey Stretch

An Introduction to Biochemistry Vol. 1 A. J. S. MCMILLAN Pp. 208. 1966. J. Audrey Stretch

Biology, Vol. 1 A. VERRINDER Pp. 274, 126 figs. 1966. Oxford: Pergamon Press. Commonwealth and International Library. 25s. (flexi-cover), 35s. (hard cover). J. Audrey Stretch

Grasses JAMES GROVES Published by the School Natural History Society, 1966, and obtainable from M. J. Wootton, Esq., 19A King's Gardens, Cranham, Upminster, Essex. 3s.

Biology Teaching in Schools Involving Experiment or Demonstration with Animals or with Pupils Compiled by J. J. BRYANT The Association for Science Education, 1967. 2s. 9d.

Handbook of Marine Biology for Borth, Cardiganshire A compilation of results and work completed by members of King Edward's School, Birmingham. Obtainable from the School. 6s. 6d.

Clarendon Biographies (16) Charles Darwin R. C. OLBY Pp. 64, 3 figs, 12 plates. London; Oxford University Press, 1967. 9s. 6d. (boards), 5s. (limp).

New Questions in O-Level Biology (Book 2) Plants and Invertebrates J. J. HEAD Pp. 70, illustrated. London: Oliver & Boyd, 1967. 6s. (Teachers' guide. Pp. 32. 5s.)

Revision Exercises in Biology J. D. MAUNDER and C. JOHNSTON Pp. xiii + 130, illustrated. Oxford: Pergamon Press, 1967. 8s. 6d.     

A Pigment-producing Spoilage Bacterium Responsible for Violet Discoloration of Refrigerated Market Milk and Cream

A psychrophilic strain of bacteria identified as Chromobacterium lividum was established as the causative agent of an outbreak of violet discoloration in refrigerated, pasteurized retail milk and cream.

The organism was rod-shaped, gram-negative, and produced viscid colonies with abundant violet pigment on Tryptone glucose yeast extract agar. Growth was abundant at 4 C but none occurred at 37 C. Growth in milk was characterized by a dark violet ring at the surface after a few days, and the deep violet color gradually extended through the product in older cultures. Some proteolysis occurred. The pigment appeared to be similar to that of other known species of Chromobacterium and assisted in identification of the genus of the causative organism.

The isolated strain of C. lividum was destroyed by exposure to 56 C for 5 min which suggested postpasteurization contamination as the source of the spoilage organism in commercial milk and cream.

     

Chlorinated pesticide residues in wild bird eggs

THE FORAGING ACTIVITY OF SNOW BUNTINGS WINTERING INLAND IN SCOTLAND, by C. J. Henty

THE ORIGINS OF SHELDUCKS MOULTING ON THE FORTH, by M . W. Pienkowski and P. R. Evans

PROLONGED PARENTAL CARE IN HERRING GULLS NESTING IN TOWNS IN EAS'1ERN SCOTLAND, by Dr W. R. P. Bourne

TRENDS IN ACCURACY OF COUNTING BIRDS, by A. J. Prater

BROWN TROUT AMONG FOOD REMAINS IN A PEREGRINE'S NEST, by D. N. Weir     

Bubbles: A Many-Sided Project

Abstract

Seed to Civilization/The Story of Man's Food by Charles B. Heiser, Jr., W. H. Freeman and Co., 660 Market Street, San Francisco, Calif. 94104, 1973, 243pp., references and index, $7.50. Reviewed by Robert C. Hayden

A Guide to the National Parks/Their Landscape and Geology by William H. Matthews III, Doubleday/Natural History Press, Garden City, New York, 1973, 529pp., selected readings, glossary and index, $5.95. Reviewed by Robert C. Hayden

Wandering Lands and Animals by Edwin H. Colbert, E. P. Dutton, 201 Park Avenue South, New York, N.Y. 10003, 1973, 32pp., bibliography, glossary and index, $12.50. Reviewed by Robert C. Hayden

Astronomy in Color by Peter Lancester Brown, The MacMillan Co., 866 Third Avenue, New York, N.Y. 10022, 1972, 265pp., appendices, glossary and index, $4.95. Reviewed by Robert C. Hayden

The Facts of Flight by Jerry Grey, a Franklin Institute book, Westminster Press, Philadelphia, Penn., 1973, 135pp., glossary and index. Reviewed by Robert C. Hayden

Zoos are News/Conservation or Extinction? by Cyril Bracegirdle, Abelard-Schuman Ltd., 257 Park Avenue South, New York, N.Y. 10010, 1973, 176pp., index, $5.95. Reviewed by Robert C. Hayden     

Reviews

The Technique of Wildlife Cinematography, by J. Warham. Focal Press, London, 1966. 42/-. 222 pages, 42 photos, text-figures.

A Field Guide to the Bird of Britain and Europe, by R. Peterson, G. Mountfort, and P. A. D. Hollom (revised and enlarged edition).Collins, London, 1966. 30/-. 344 pages, 66 plates, text-figures and map.

Les Rapaces Diurnes et Nocturnes d'Europe, by P. Géroudet. Editions Delachaux & Niestlé, Neuchatel, Switzerland, 1965. 426 pages, 48 plates (24 in colour), 50 text-figures.

The Birds of Berkshire and Oxfordshire, by M. C. Radford. Longmans, 1966. 42/-. 212 pages, 19 photographic plates, frontispeiece by R. A. Richardson.

Land and People: The Countryside for Use and Leisure, edited by Rosemary Jellis. B.B.C. Publications, 1966. 6/-. 142 pages.     

Regulation by Lipids of Plant Microsomal Enzymes: III. Phospholipid Dependence of the Cytidine-Diphospho-Choline Phosphotransferase of Potato Microsomes

Cytidine-diphospho-choline diacyl-glycerol phosphorylcholine phosphotransferase activity was demonstrated in potato (Solanum tuberosum L.) microsomes and the incorporation of cytidine-diphospho[¹⁴C]choline into phosphatidylcholine was characterized by the time course of ¹⁴C incorporation and the effect of microsomal protein concentration on choline incorporation.

Potato microsomes were progressively delipidated by treatments (2 min at 0°C) with increasing amounts of phospholipase C from Bacillus cereus. A decrease in choline phosphotransferase activity was observed in parallel with the progressive hydrolysis of membrane phospholipids. A 70% (or more) phospholipid hydrolysis provoked the total inactivation of the enzyme.

Adding back exogenous phospholipids (in the form of liposomes) to phospholipase C-treated membranes restored the enzymic activity. Restoration could be obtained with egg yolk phospholipids as well as with potato phospholipids. Restoration was time dependent and completed after 10 minutes; restoration was also dependent on the quantity of liposomes added to lipid-depleted membranes: the best restorations were obtained with 1 to 2.5 milligrams of phospholipid per mg of microsomal protein; higher phospholipid to protein ratios were less efficient or inhibitory.

These results clearly demonstrate the phospholipid dependence of the cytidine-diphospho-choline phosphotransferase from potato microsomes.

     

Chaperone-Mediated Autophagy and Aging: A Novel Regulatory Role of Lipids Revealed

A wide pool of cytosolic proteins is selectively degraded in lysosomes by chaperone-mediated autophagy (CMA). Binding of these proteins to a receptor at the lysosomal membrane is the limiting step in CMA. Levels of this receptor are tightly regulated through changes in its degradation, multimeric organization and dynamic distribution between the lysosomal membrane and lumen. We have now reported that subcompartmentalization of the receptor in discrete lipid microdomains at the lysosomal membrane regulates its engagement in each of these processes — degradation, multimerization and membrane retrieval. Changes in the lipid composition of the membrane thus affect the dynamics of the receptor and, consequently, CMA activity. As an example of CMA dysfunction resulting from perturbation of the lipid composition of the lysosomal membrane, we discuss here a second study in which we analyzed the changes in the dynamics of the receptor during aging. CMA activity decreases with age primarily due to a decrease in the levels of the CMA receptor at the lysosomal membrane. Now we have found that age-related alterations in the lipid composition of the discrete microdomains at the lysosomal membrane are behind the reduced lysosomal levels of the receptor and, consequently, the declined CMA activity that occurs during aging.

Addendum to:

Altered Dynamics of the Lysosomal Receptor for Chaperone-Mediated Autophagy with Age

R. Kiffin, S. Kaushik, M. Zeng, U. Bandyopadhyay, C. Zhang, A.C. Massey, M. Martinez-Vicente and A.M. Cuervo

J Cell Sci 2007; 120:782-91

and

Lysosome Membrane Lipid Microdomains: Novel Regulators of Chaperone-Mediated Autophagy

S. Kaushik, A.C. Massey and A.M. Cuervo

EMBO J 2006; 25:3921-33     

Dependence of Basipetal Polar Transport of Auxin upon Aerobic Metabolism

The movement of IAA-¹⁴C through coleoptile segments of Avena and Zea has been investigated under aerobic and anaerobic conditions. The results are as follows: Zea. Using a 5-mm segment and a 2-hour transport period anaerobic conditions reduced the total uptake of ¹⁴C from an apical donor by 74% and the proportion of the total found in the receiving block by at least 45%. Anaerobic conditions reduced total uptake from a basal donor by 58% but no ¹⁴C reached the apical receiving block in either air or N₂. Uptake from apical and basal donor blocks in N₂ is closely similar.

The presence of ¹⁴C in the basal receiving blocks, and its absence in the apical receiving blocks, in N₂ suggests that even in anaerobic conditions movement of IAA is polarized basipetally, although the movement occurs at only a fraction of the rate found in air.

Anaerobic conditions induced a similar reduction in basipetal movement of IAA in upper and lower 5-mm segments taken from the apical 10 mm of a Zea coleoptile.

Using 10-mm Zea segments no ¹⁴C was recovered in the receiving blocks at the basal end of the segment after 2 and 4 hours in N₂ whereas large amounts were recovered in air.

Avena: Using 5-mm segments and a 2-hour transport period the total uptake of ¹⁴C from an apical donor is reduced by 83%. Movement of ¹⁴C into the basal donor is totally inhibited in N₂. Total uptake of ¹⁴C from a basal donor is reduced by 61% in nitrogen and no ¹⁴C reached the apical receiving blocks regardless of the atmospheric conditions.

A time course for the movement of ¹⁴C into the basal and apical receiving blocks through 5-mm segments showed that in air the amount in the basal receivers increased for 4 hours and then remained approximately uniform. In N₂ no significant ¹⁴C reached the receivers until 6 to 8 hours after the application of donors but even then the amounts were about 12 to 14% of that in aerobic receivers. Movement of ¹⁴C into apical receivers was similar in air and in nitrogen and even after 6 to 8 hours the amount of radioactivity barely reached significant levels.

     

The Birds of High-Level Woodlands. The Breeding Community

Winter territory in the Stonechat, by J. S. Phillips

Cloaca-pecking and copulation in the Dunnock, by C. J. O. Harrison and F. G. Binfield, A.S.P.E.B.A.

A possible source of error in raptor food analysis, by Douglas N. Weir     

Experimenters

Understanding the Masters, A &; W Visual Library, 95 Madison Ave., N.Y.C. 10016, $2.95 per volume

Raku Pottery…………by Robert Piepenburg, Collier Books, New York City 10022 $6.95

Soft Jewelry…………by Nancy Howell-Koehler, Davis Publications, Inc. Worcester, MA 01608 $10.95

Bookbinding as a Handcraft… by Manly Banister, Sterling Publishing Co., Inc. New York City 10016 $12.95

The Art Lover's Cookbook edited by Marie Welsh, Summit Art Center Summit, NJ 07901 $5.95     

Activation of Intracellular Proteinases of Yeast

The existence of the inactive precursors of yeast proteinases B and C was confirmed in the autolysate of baker’s yeast and they were named as pro-proteinases B and C, respectively. The active and inactive forms of proteinase C were two distinct proteins, separable by chromatographical procedures. The two precursors were markedly activated by incubation at pH 5 or by treatment with denaturing agents, e.g. urea, dioxane, acetone and certain alcohols.

These activations were also observed with extracts from acetone-dried cells and from mechanically destructed cells, but the activation of proteinase A was not demonstrated under any conditions tested. Therefore, it was assumed that most of proteinases B and C exist in vivo as inactive precursors, whereas proteinase A originally exists in an active form.

Pro-proteinase C, the latent form of yeast proteinase C, was partially purified from the autolysate of baker’s yeast. It was strongly activated by incubation at pH 5 or by treatment with urea or dioxane. The former activation was prevented by treatment to inactivate yeast proteinase A, which co-existed with the pro-enzyme in the present preparation, but was promoted by addition of purified proteinase A. Thus, it was confirmed that A could activate pro-proteinase C. Furthermore, it was found that activation could be caused by extremes in pH or by heating to 55~60°C, accompanied by the simultaneous destruction of the enzyme produced. Pro-proteinase C was stable over a range of pH 5 to 8 after 60 min incubation at 50°C.     

Mycothiol peroxidase MPx protects Corynebacterium glutamicum against acid stress by scavenging ROS

Objectives

To investigate mycothiol peroxidase (MPx) of Corynebacterium glutamicum that is a novel CysGPx family peroxidase using both the mycoredoxin and thioredoxin reducing systems as proton donors for peroxide detoxification and may be involved in the relief of acid stress.

Results

A Δmpx mutant exhibited significantly decreased resistance to acid stress and markedly increased accumulation of reactive oxygen species (ROS) and protein carbonylation levels in vivo. Over-expression of mpx increased the resistance of C. glutamicum to acid stress by reducing ROS accumulation. The stress-responsive extracytoplasmic function-sigma (ECF-σ) factor, SigH, mediated acid-induced expression of mpx in the wild-type under acid conditions, which in turn directly contributed to tolerance to acid stress.

Conclusion

MPx is essential for combating acid stress by reducing intracellular ROS levels induced by acid stress in C. glutamicum, which adds a new dimension to the general physiological functions of CysGPx.