THE RATIO OF CALCAREOUS AND ORGANIC SHELL COMPONENTS OF FRESHWATER SPHAERIID CLAMS IN RELATION TO WATER HARDNESS AND TROPHIC CONDITIONS

Shells from 14 populations of sphaeriid clams including Sphaeriumstriatinum, S. simile, Pisidium walkeri, Musculim partumeiumand M. iransversum were analyzed for organic carbon (µgCmg^–1 shell), nitrogen (µg,N mg^–1 shell) andCaCO_s (%CaCO₃ of total clam dry weight). Habitat waters wereassessed for total hardness (expressed as ppm CaCo₃), ppm Ca,ppm Mg, conductivity (µmho) and suspended organic Carbon(µgCl^–1). For all populations, shell organic C andN are positively correlated and there is an inverse relationshipbetween the amounts of shell CaCO₃ and shell organic carbon.Trophic considerations give the best correlation with shelltype at the generic level of consideration since species ofMusculium are found at the opposite end of the trophic scale(eutrophic) from all other populations studied. For S. striatinum,the most extensively studied species, the amount of shell CaCO₃is inversely related to water hardness. The selection of shellsin the Sphaeriidae is discussed in relation to structural-functionalneeds and habitat conditions ¹ Present Address: Department of Biology, Syracuse University,Syracuse, New York 13210, U.S.A. ² Present Address: Department of Zoology, Miami University,Oxford, Ohio 45056, U.S.A. (Received 5 December 1978;     

Expression in Yeast of a Fusion Gene Composed of the Promoter of a Heat-Shock Gene from Arabidopsis and a Bacterial Gene for {beta}-Glucuronidase

Production of a functional ß-glucuronidase (GUS) proteinwas induced by exposure of exponentially growing yeast cellsto heat shock after transformation of the GUS gene under thecontrol of the promoter of the heat-shock gene, HSP18.2, fromArabidopsis. Yeast cyr and bcy mutations appeared to have essentiallyno effect. ¹Present Address: Laboratory of Plant Molecular Biology, TheRockefeller University, 1230 York Avenue, New York, NY 10021-6399,U.S.A.     

Localization and Binding Characteristics of a High-Affinity Binding Site for N--Acetylchitooligosaccharide Elicitor in the Plasma Membrane from Suspension-Cultured Rice Cells Suggest a Role as a Receptor for the Elicitor Signal at the Cell Surface

A high-affinity binding site for N-acetylchitooligosac-chlarideelicitor was found to localize in the plasma membrane from suspension-culturedrice cells. Binding kinetics as well as the specificity of thisbinding site corresponded well with the behavior of the ricecells to the editor. These characteristics suggest that thebinding site represents a functional receptor for N-acetylchitooligosaccharideelicitor in rice. ²Present address: Okinawa Prefectural Livestock ExperimentalStation, 2009-5 Shoshi, Nakijin-son, Okinawa, 905-04 Japan. ³Present address: School of Hygiene and Public Health, The JohnsHopkins University, 615 North Wolfe Street, Baltimore, Maryland,21205 U.S.A. ⁴Present address: University of Tenessee, Microbiology, knoxville,Tennessee, 37996 U.S.A.     

Plant Cell Wall Proteins: Partial Characterization of Maize Wall Proteins With Putative Roles in Auxin-Induced Growth

Antibodies raised against cell wall proteins inhibited auxin-inducedgrowth of Zea mays L. coleoptile segments. The total complementof proteins isolated from the cell walls of Zea mays seedlingswas fractionated by cation exchange and gel filtration chromatography.A procedure was developed to evaluate these cell wall-proteinfractions for their ability to reverse growth inhibition causeby specific antibody binding. Inhibition of growth was attributedto specific antibody-antigen interaction based on the observationsthat only serum containing antibodies against certain cell wallproteins inhibited growth, that gamma globulins purified fromappropriate serum samples inhibited growth, and that a specificsubfraction of isolated cell wall proteins precipitate the growthinhibiting antibody. Antigens which generated growth inhibitoryantibodies were identified as an acidic group of proteins withapparent relative molecular masses in the range of 20–25kDa. This subfraction of cell wall proteins was not effectivein hydrolyzing cell wall polysaccharides. A small amount ofcarbohydrate was found associated with this fraction and mayreflect some degree of glycosylation of some of the proteins ¹Supported in part by National Science Foundation Research GrantPCM 7818588 ²Present Address: USDA-ARS, U.S. Dairy Forage Research Center,University of Wisconsin, Madison, WI 53706 ³Present Address: Department of Vegetable Crops, Universityof California, Davis, CA 95616 (Received November 2, 1987; Accepted March 31, 1988)     

Swelling of Etiolated Oat Protoplasts Induced by cAMP and Red Light

Etiolated oat protoplasts were treated with dibutyryl cAMP tostudy possible function of cAMP in the development by measuringthe protoplast swelling. The mean diameter of protoplasts inthe absence of any chemical treatment was 33.58±1.26(SE) µm, which increased to 36.96±0.86 µmin the presence of 100 µM dibutyryl cAMP. Prostacyclin,a potent activator of adenyl cyclase, also showed a significantswelling effect (diameter 38.01±0.98 µm). Red lightalso elicited the swelling of protoplasts (40.26±0.8µm). ¹Present address: Department of Biology, Pusan National University,Pusan 607, Korea. ²Present address: Department of Horticulture, Cheju NationalUniversity, Cheju 590, Korea. ³Present address: Department of Biological Sciences, Texas TechUniversity, Lubbock, TX 79409, U.S.A. (Received June 29, 1985; Accepted November 18, 1985)     

EFFECT OF CARBONYL CYANIDE PHENYLHYDRAZONE ON CATION UPTAKE IN EXCISED BARLEY ROOTS

The generally-accepted characteristics of ion transport in planttissue do not apply completely in the case of zinc uptake. Inthis case, 5x1^–5 M CCP (which completely stops rubidiumuptake in barley roots) shows little inhibitory effect. In thisrespect it is like DNP which also shows little influence onzinc uptake in this concentration. ¹ Present Address: Department of Botany and Plant Pathology,University of Minnesota, St. Paul, Minnesota, U.S.A.     

Properties of S-adenosyl-L-methionine-magnesium-protoporphyrin IX methyltransferase from barley

S-Adenosyl-L-methionine-magnesium-protoporphyrin IX methyltransferase(EC 2.1.1.11 [EC] ) is present in greening barley seedlings associatedwith the particulate fraction. This enzyme was purified 20 foldusing protamine and ammonium sulfate precipitation. The enzymewas active over a wide pH range with highest activity at pH7.5. The Km values for Mg-protoporphyrin IX and S-adenosylmethioninewere 48 and 39 µM, respectively; S-adenosylethionine andS-adenosyihomocysteine were competitive inhibitors with respectto S-adenosylmethionine; hemin inhibition was non-competitivewith respect to Mg-protoporphyrin IX; thiol compounds exhibiteda stimulatory effect on enzyme activity. The properties of theenzyme are discussed and compared with the enzyme from otherorganisms. ¹ This research was supported in part by the Utah State AgriculturalExperiment Station. ² Present address: Department of Chemistry, Boston University,Boston, Massachusetts, U. S. A. ³ Present address: Department of Biochemistry and Microbiology,Faculty of Pharmacy, Comenius University, Bratislava, Czechoslovakia. (Received February 20, 1978; )     

Activation Energies of Reactions Catalyzed by the Nitrate Reductase from Chlorella vulgaris

The thermal dependence of two of the reactions catalyzed bythe nitrate reductase from Chlorella vulgaris was determined.The activation energies for NADH:nitrate oxidoreductase (EC1.6.6.1 [EC] ) and NADH:Cytochrome c oxidoreductase (EC 1.6.99.3 [EC] )are 42.1 kJ?mol^–1 and 21.5 kJ?mol^–1, respectively.Since the thermal dependency of the two enzymes is different,ratios of the activities will vary with temperature. The importanceof both rigorous thermal control during nitrate reductase assaysas well as the need to specify the temperature at which theratio of activities for the enzyme are clearly established. ¹Present Address: Cropping Systems Research Laboratory, USDA-ARS,Route 3, Box 215, Lubbock, TX 79401, U.S.A. (Received November 25, 1987; Accepted March 2, 1988)     

ORNITHINE CYCLE ENZYMES IN THE BLUE-GREEN ALGA NOSTOC MUSCORUM

Cell-free extracts of a bacteria-free culture of Nostoc muscorumwere used to demonstrate the occurrence of part of the KREBS-HENSELEITornithine cycle in blue-green algae. Evidence is presented forthe conversion of ammonia and bicarbonate to carbamyl phosphateand the coupling of carbamyl phosphate to ornithtne to yieldcitrulline. Attempts to demonstrate the conversion of citrullineto arginine were not successful. ¹Present address: Scripts Institute of Oceanography, Universityof California, La Jolla, California, U.S.A. ²Present address: Department of Biochemistry and Nutrition,The University of Texas Medical Branch, Galveston, Texas, U.S.A.     

Vertical migration and diel activity patterns of hydromedusae: studies in a large tank

Vertical distributions and swimming behaviors of 7 species ofhydromedusae (Aequorea victoria, Bougainvillia principis, Gonionemusvertens, Mitrocoma cellularia, Phialidium gregarium, Polyorchispenicillatus, and Stomotoca atra) were observed over 24-h periodsin a 2 m high, 1500 1 transparent tank. In this tank, most speciesperformed well-marked diel vertical migrations that were mediatedby swimming. Manipulation of the light regime showed the didswimming behaviors to be light-dependent rather than intrinsic,even in species that do not possess recognized photoreceptors.Correlations between vertical migration and spawning times forseveral species of medusae suggest that in cases when verticalmigration reduces the distances between individuals (e.g., inmass movements to the surface) just prior to spawning, enhancedfertilization success may result from such movements. ¹Present address: Friday Harbor Laboratories, Friday Harbor,WA 98250, USA.     

Environmental Control of Carbohydrate and Lipid Synthesis in Euglena

Dark-grown and light-grown nitrogen deficient Euglena accumulatedcarbohydrates and lipids under heterotrophic and phototrophicconditions. Although cellular lipid content increased, lipidas a percentage of dry weight was unaltered. Nitrogen deficientand sufficient heterotrophic cultures synthesized equal amountsof lipid per mole of exogenous carbon. Nitrogen deficiency doesnot alter the partitioning of available carbon between the synthesisof lipid and other cellular constituents but simply inhibitscell division so that the carbohydrate and lipid produced aredivided among fewer cells increasing the quantity of storageproducts per cell. Cellular chlorophyll content decreased onlywhen nitrogen deficient cells were maintained at high lightintensities suggesting that chlorophyll loss is due to a reductionin the rate of resynthesis of chlorophyll destroyed throughphotooxidative damage. Anaerobiosis triggered lipid synthesisand promoted carbohydrate breakdown in the dark and light. Evenafter six days of nitrogen deficiency, anaerobiosis triggeredadditional lipid accumulation and carbohydrate breakdown. Incontrast to nitrogen deficiency, anaerobiosis produced a preferentialincrease in the percentage of dry weight as lipid. This increasewas due as much to a decrease in cellular dry weight as it wasto the preferential utilization of available carbon for lipidsynthesis. ¹Present Address: The Mycology Center, Washington UniversitySchool of Medicine, St. Louis, MO 63178, U.S.A. ²Present Address: Department of Biology, University of Tampa,Tampa, Florida 33060, U.S.A. (Received September 16, 1987; Accepted January 18, 1988)     

Protein Synthesis Linked to Respiration and Phosphorylation in Intact Euglena Mitochondria

Highly purified condensed mitochondria obtained from bleachedmutant. W₁₀BSmL of Euglena gracilis Klebs var bacillaris Coriincorporate [³⁵S]methionine into protein when fortified withmalate, ADP, Mg²⁺, phosphate and a sucrose osmoticum. Twentyto twenty-five polypeptide bands were found to be labeled inorganello when the labeled protein was subjected to sodium dodecylsulfatepolyacrylamide gel electrophoresis. Methionine incorporation,but not respiration or oxidative phosphorylation, was blockedby chloramphenicol and other 70S ribosomal translation inhibitorsbut cycloheximide and ribonuclease were without effect. Inhibitorsof electron transport and uncouplers of oxidative phosphorylationwere excellent inhibitors of protein synthesis. Thus, thesemitochondrial preparations carry out protein synthesis in organellothat is linked to respiration and oxidative phosphorylation. ¹Present address: VA Hospital Outpatient Clinic, 17 Court St.,Boston, MA 02115, U.S.A. ²Present address: Laboratories de Microbiologia e Inmunologia,Universidad Catolica de Chile, Casilla 114-D, Santiago, Chile. ³Present address: Botany Department, University of Massachusetts,Amherst, MA 01003, U.S.A. (Received June 17, 1985; Accepted October 28, 1985)     

Protein Kinase Inhibitors Inhibit Stimulation of Inositol Phospholipid Turnover and Induction of Phenylalanine Ammonia-Lyase in Fungal Elicitor-Treated Tobacco Suspension Culture Cells

Elicitor prepared from Phytophthora nicotianae stimulated inositolphospholipid turnover and induced phenylalanine ammonia-lyaseactivity in tobacco suspension culture cells [Kamada and Muto(1994) Plant Cell Physiol. 35: 397]. Protein kinase inhibitors,K252a and staurosporine inhibited both responses. These resultssuggest that inositol phospholipid turnover plays an importantrole in PAL induction through protein kinases. In addition,their mode of inhibition were different, proposing that severaltypes of protein kinases are involved in these elicitor-inducedresponses. ¹Present address: The Johns Hopkins University School of Hygieneand Public Health, 615 N. Wolfe St., Baltimore, Maryland 21205,U.S.A. ²Present address: Nagoya University BioScience Center and GraduateSchool of Agricultural Sciences, Nagoya University, Chikusa-ku,Nagoya, 464-01 Japan.     

ORGANIC CARBON, ENVIRONMENTAL FACTORS AND GROWTH IN THE SMALL EURYHALINE GASTROPOD, POTAMOPYRGUS JENKINSI (SMITH)

A method of analysing small invertebrates for organic carbon(in the range 6.0 to 1000 µg) is described. The relationshipsbetween organic carbon content, total dry weight and shell lengthwere detemined for Potamopyrgus jenkinsi living in differentcombinations of salinity and temperature. Differences in organiccarbon content were found in relation to weight at differentgrowth temperatures. This work is a further confirmation ofthe usefulness of organic carbon content as a measure of thegrowth or biomass of small invertebrates. ^*Present Address: School of Biology, University College, P.M.B.5323, Port Harcourt, Nigeria. (Received 27 April 1977;     

Induction of Cold Hardiness by Salt Stress Involves Synthesis of Cold- and Abscisic Acid-Responsive Proteins in Potato (Solanum commersonii Dun)

Salt stress has been found to increase frost tolerance in someherbaceous species. In an attempt to understand the molecularbasis of the frost tolerance induced by salt stress, the effectof salt (100 mM NaCl) on total proteins in stem-cultured potatoplantlets (Solarium commersonn Dun) was analyzed on two-dimensionalgels. Nine salt-induced proteins were identified after 24 hsalt treatment, at which time cold hardiness increased by threedegrees. Direct comparisons of the proteins with those inducedby cold- and abscisic acid(ABA)-treatments revealed that fiveof the salt-induced proteins were also induced by cold(4°/2°C)-treatmentand seven were also induced by ABA(40µM)-treatment. Threeproteins (M_rr/pls 13/7.0, 27/6.6 and 48/6.9) were induciblein both cold- and ABA-treatments in association with frost hardening.After 6 h salt treatment, endogenous ABA levels in plantletleaves showed a transient six-fold increase before cold hardinessdeveloped. The results suggest that salt-induction of cold hardinessinvolves the synthesis of cold and ABA-responsive proteins andthe alteration of protein synthesis is mediated by ABA elevatedupon salt stress. This study also suggests that a subset ofproteins induced by cold and ABA-treatments are related to saltstress. ¹Scientific Journal Series Paper No. 20787 of the MinnesotaAgricultural Experimental Station, St. Paul, MN 55108, U.S.A. ²Present address: Department of Biochemistry Willard Hall, KansasState University, Manhattan, KS 66506, U.S.A. ³Present address: Via G.B. Marino 13, 80125-Napoli, Italy ⁴Present address: Institute of Biological Chemistry, WashingtonState Univ., Pullman, WA 99164, U.S.A.     

Periplasmic location of dissimilatory nitrate and nitrite reductases in a denitrifying phototrophic bacterium, Rhodopseudomonas sphaeroides forma sp. denitrificans

The localization of dissimilatory nitrate and nitrite reductasesof a denitrifying phototrophic bacterium, Rhodopseudomonas sphaeroidesforma sp. denitrificans, was investigated. Nitrate and nitritereductases were located in the periplasmic space of the bacteriumgrown anaerobically in the presence of nitrate either in lightor in darkness. Chromatophores showed nitrate and nitrite reductaseactivities when dithionite-reduced benzyl viologen was an electrondonor; this suggests that the enzymes were trapped inside thevesicles. ¹Present address: Japanese Red Cross Central Blood Center, Hiroo4-1-31, Shibuyaku, Tokyo 150, Japan. ²Present address: Plant Growth Laboratory, University of California,Davis, California 95616, U.S.A. (Received November 7, 1979; )     

Cloning of cDNA of Prunus serotina (R)-(+)-Mandelonitrile Lyase and Identification of a Putative FAD-Binding Site

A full-length cDNA clone encoding the flavoprotein (R)-(+)-mandelonitrilelyase was isolated from a black cherry (Prunus serotina) cDNAexpression library and sequenced. A putative FAD-binding sitewas identified near the N-terminus of this enzyme by comparingits deduced amino acid sequence with those of other FAD- andNAD-binding proteins. ¹Present address: Department of Pharmacology, University ofMedicine & Dentistry of New Jersey, Piscataway, New Jersey08854, U.S.A.     

Morphogenesis of Schizophyllum commune III.Activity of inhibitors of energy metabolism

The effect of azide, 2,4-dinitrophenol, malonate and 2-deoxyglucoseon the physiology and morphology of normal and mutant strainsof Schizophyllum commune was studied. Normal, thin and puffstrains showed a decrease in dry weight and an increase in glucoseutilization in response to azide, dinitrophenol and 2-deoxyglucose.Streak was less sensitive to azide and dinitrophenol and almostcompletely resistant to 2-deoxyglucose. Numerous morphogeneticeffects were caused by the inhibitors. These included the inductionof certain aspects of the morphology of the common-A sexualreaction in normal and thin homokaryons by 2-deoxyglucose, areversion to normal morphology by thin strains in response toazide and dinitrophenol, and a morphogenetic insensitivity tothe inhibitors by the streak mutants. A discussion of the relationshipof these effects to the control of morphology in S. communeis given. ¹This investigation was supported in part by Research GrantAI-06570 from the National Institute of Allergy and InfectiousDiseases of the U. S. Public Health Service and by Grant No.GB-3613 from the National Science Foundation (U.S.A.). ²Present Address: Department of Biology, State College at Bridgewater,Bridgewater, Massachusetts 02324, U. S. A.     

A Mutant of Arabidopsis thaliana That Defines a New Locus for Glycine Decarboxylation

A novel photorespiratory mutant of Arabidopsis thaliana, designatedgld2, was isolated based on a growth requirement for abnormallyhigh levels of atmospheric CO₂. Photosynthetic CO₂ fixationwas inhibited in the mutant following illumination in air butnot in atmosphere containing 2% O₂. Photosynthetic assimilationof ¹⁴CO₂ in an atmosphere containing 50% O₂ resulted in accumulationof 48% of the soluble label in glycine in the mutant comparedto 9% in the wild type. The rate of glycine decarboxylationby isolated mitochondria from the mutant was reduced to 6% ofthe wild type rate. In genetic crosses, the mutant complementedtwo previously described photorespiratory mutants of A. thalianathat accumulate glycine during photosynthesis in air due todefects in glycine decarboxylase (glyD, now designated gld1)and serine transhydroxymethylase (stm). Because glycine decarboxylaseis a complex of four enzymes, these results are consistent witha mutation in a glycine decarboxylase subunit other than thataffected in the gld1 mutant. The two gld loci were mapped tochromosomes 2 and 5, respectively. ³Present address: Department of Crop and Soil Sciences, MichiganState University, East Lansing, MI 48824, U.S.A. ⁴Present address: Department of Applied Bioscience, Facultyof Agriculture, Hokkaido University, Kita-Ku, Sapporo, 060 Japan ⁵Present address: Department of Biology, Carnegie Institutionof Washington, 290 Panama Street, Standford, CA 94305, U.S.A.