A Conceptual Framework for Biology Part II

This essay is part of the seventh yearly presentation of aneducational project of the American Society of Zoologists, Scienceas a Way of Knowing. It is also the second part of a "ConceptualFramework for Biology." Part II begins a discussion of evolutionand deals with an overview of living metazoans and then discussestheir history during the Phanerozoic Eon. Part III will completethe discussion of evolution and then consider "Classification,"Ecology," "Geographic Distribution," "Methods of Science,"and "Science and Human Welfare." The intended readers are thosewho teach the first-year biology courses in colleges and universitiesas well as teachers of the precollege grades.     

Analysis of Lipids in Prochloron sp.: Occurrence of Monoglucosyl Diacylglycerol

Prochloron contained monogalactosyl diacylglycerol, digalactosyldiacylglycerol, sulfoquinovosyl diacylglycerol, phosphatidylglyceroland, as a minor component, monoglucosyl diacylglycerol, butno phosphatidylcholine. With respect to the lipid and fattyacid compositions, this alga is similar to the blue-green algaerather than the chloroplasts of eukaryotic plants. ¹ Present address: Department of Biology, Faculty of Science,University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113, Japan. (Received August 24, 1982; Accepted November 18, 1982)     

The Hydration-Induced Ca2+ Release Is a General Phenomenon in Characeae

When an internodal cell of Nitella axilliformis that had beentreated with 10 mM KCl and 1 mM EGTA was examined for transcellularosmosis, an increase in the cytosolic concentration of Ca²⁺on the endoosmotic side was observed, as was the case in Nitellaflexilis even though the increase was much smaller in Nitellaaxilliformis. The hydration-induced calcium release (HICR) wasalso observed in other species of Characeae, namely, Chara corallinaand Nitellopsis obtusa. HICR was also demonstrated in cytoplasmisolated from Nitella axilliformis and Chara corallina as fromNitella flexilis. Thus, it appears that HICR is not specificto Nitella flexilis but may be a general phenomenon in Characeae. ²Present adress: Department of Biology, Faculty of Science,Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba, 263 Japan     

Separation of hormone-sensitive yeast cells by density gradient centrifugation

Cells in cultures of haploid strains of Saccharomyces cerevisiaein stationary phase were separated into interface fraction andpellet fraction by density gradient centrifugation. Cells inpellet fraction expanded in response to yeast sexual hormoneand animal sex hormones, whereas cells in interface fractiondid not. ¹Present address: Department of Biology, Faculty of Science,Osaka City University, Sumiyoshi-ku, Osaka, Japan (Received July 16, 1970; )     

Partial purification and some properties of an L-{alpha}-amino-S-caprolactam-hydrolyzing enzyme from Cryptococcus laurentii

A new L-amlnolactam-hydrolyzing enzyme was partially purifiedfrom cells of Cryptococcus laurentii which can grow on L-aminolactamas a carbon and nitrogen source. The enzyme required a bivalentmetal ion, such as Mn²⁺ or Mg²⁺, and its molecular weight wasroughly estimated to be 1.5?10⁵ Some other properties were alsostudied. ¹ Present address: Department of Biology, Faculty of Science,Osaka City University Sumiyoshi-ku, Osaka 558, Japan. (Received June 20, 1977; )     

Induction of nitrate and nitrite reductases in Anabaena cylindrica

Induction of nitrate and nitrite reductases in Anabaena cylindrica(FOGG strain) was investigated. At various stages of algal growthin the presence of nitrate or nitrite, the levels of these enzymeswere determined using cell-free preparations. Nitrate and nitritereductases were induced by the respective substrates. Nitratedid not act either as an inducer or as a repressor of nitritereductase. ¹This work was supported by grant No. 8814 from the Ministryof Education ²Department of Biology, Faculty of Science, Tokyo MetropolitanUniversitySetagaya-ku, Tokyo, Japan (Received June 18, 1970; )     

The presence of gibberellin A20 in Stevia rebaudiana and its significance for the biological activity of steviol

Gibberellin-like substances of stems and leaves from Steviarebaudiana were analyzed and gibberellin A₂₀ was identifiedby gas chromatography-mass spectrometry. The presence of GA₂₀in S. rebaudiana is significant for the interpretation of thegibberellin activity of steviol. It indicates that steviol,the C-13 hydroxykaurenoic acid, may function as a precursorfor C-13 hydroxy-gibberellins and not as a gibberellin analog. ¹ This work was supported by National Science Foundation GrantGB 17304 to M. R. and by a Research Grant-in-Aid from SigmaXi to L. M. A. The research described is from a dissertationsubmitted by L. M. A. in partial fulfillment of the requirementsfor the Ph.D. degree. ² Present address: Laboratory of Plant Morphogenesis, Departmentof Biology, Manhattan College, Bronx, N. Y. 10471, U. S. A. (Received June 12, 1978; )     

Phytochrome Control of Its Own Synthesis in Pisum sativum

An analysis of phytochrome synthesis in Pisum seedlings by measuringthe activity of polysomal polyadenylated RNA (poly-A⁺-RNA) codingfor phytochrome apoprotein showed phytochrome control of itsown synthesis; brief red-light irradiation of pea seedlingsinhibited the activity of the RNA, and the red-light effectwas red/far-red reversible. ⁴ Permanent address: Biology Department, Faculty of Science,University of Tokyo, Hongo, Tokyo 113, Japan. (Received August 13, 1984; Accepted September 17, 1984)     

Viability of Chlamydomonas Mutants with Amino Acid Substitutions in the Precursor D1 Protein at the Carboxyl-Terminal Processing Site: an Analysis by Mixed-Culture Growth Experiments

Department of Biology, Faculty of Science, Okayama University,3-1-1, Tsushima-naka, Okayama, 700-8530 Japan In order to analyzethe influence of amino acid substitutions at the carboxyl-terminalprocessing site of the D1 precursor protein, mixed-culture growthexperiments were conducted for psbA directed mutants of Chlamydomonasreinhardtii. Wild type and D1 mutants were mixed in the sameculture and their viability was compared. Replacement of Ser-345by Gly or Val at the cleavage site markedly affected the relativegrowth rate of the mutant in the high intensity light, but notin a dim light or the darkness. This was consistent with theprevious result obtained by in vitro analysis using substitutedcarboxyl-terminal oligopeptides as substrates [Taguchi et al.(1995) J Biol. Chem. 270: 10711], This is a clear indicationthat the rate of carboxyl-terminal processing of the D1 precursorin the photosystem II reaction center is a rate-limiting stepfor growth under some environmental stress conditions. (Received June 9, 1998; Accepted September 25, 1998)     

Enzymic synthesis of floridean starch in a red alga, Serraticardia maxima

ADP-glucose: -l,4-glucan -4-glucosyltransferase was obtainedfrom a marine red alga Serraticardia maxima in a form boundwith floridean starch granules. The enzyme catalyzed the transferof glucosyl residue from ADP-glucose, UDP-glucose and GDP-glucoseto floridean starch added as a primer. ADP-glucose was the mostefficient glucosyl donor in the reaction. Maltose was producedby ß-amylolysis of the glucan synthesized by the algalenzyme. The optimum pH for enzyme activity was at 8.4. The enzymewas not obtained in a soluble form from either the chloroplastextract or the whole algal cell extract. Electron micrographsof algal cells revealed that floridean starch granules are localizedexclusively outside chloroplasts. Hence, it appears that mostof the synthetase is present outside chloroplasts. ¹ Contribution from the Shimoda Marine Biological Station, TokyoKyoiku University, No. 202. This work was supported by a Grant-in-Aidfor Cooperative Research from the Ministry of Education, Japan. ² Present address: Department of Biology, Faculty of Science,Science University of Tokyo, Kagurazaka, Tokyo 162, Japan. ³ Present address: Laboratory of Biology, Faculty of Science,Toho University, Narashino, Chiba 275, Japan. (Received May 25, 1970; )     

RESTORATION OF PHOTOCHEMICAL ACTIVITY OF ISOLATED CHLOROPLASTS LOST BY ALUMINA TREATMENT

Isolated spinach chloroplasts were ground with alumina in amortar with the addition of 0.2 M KC1 solution. This treatmentresulted in a loss of fifty to ninety per cent of the originalphotochemical activity. A petroleum benzin extract was prepared from the alumina residue.After evaporating the solvent from the extract, the residuewas dissolved in methanol. The methanol was evaporated and theresidue was suspended in distilled water and centrifuged. Thecolorless supernatant solution exhibited a reactivation effectwhen added to the alumina-treated chloroplasts. It was inferred from the difference spectrum obtained betweenits oxidized and reduced forms that the active substance inquestion is functioning as intermediary hydrogen carrier inthe HILL reaction. ¹ Contribution No. 100 from the Department of Biology, Facultyof Science, Kyushu University. (Received July 19, 1960; )     

Effects of CaCl2-washing on EPR Signals of Cytochrome b559 in Photosystem II Preparation from Spinach Chloroplasts

Washing of PS II preparation by 1 M CaCl₂ inactivates oxygenevolution without loss of bound manganese [Ono and Inoue (1983)FEBS Lett. 164: 255]. Most of the high-potential Cyt b₅₅₀, whichamounts to about a half of the total Cyt b₅₅₉ in untreated preparation,was converted to its low-potential form by CaCl₂-washing. Theeffect was similar to that of Tris-washing. The peak positionof the g_s band of the EPR spectrum of the CaCl₂-washed preparation(g=2.95) was the same as that of the low potential form of untreatedpreparation but was slightly different from that of the Tris-washedor heat-treated preparation (g=2.98). ¹ Present address: Department of Biology, Faculty of Science,Tokyo Metropolitan University, Fukazawa 2-1-1, Setagaya, Tokyo158, Japan. (Received November 14, 1984; Accepted January 30, 1985)     

N-Acetylglucosamine-Containing Glycopeptide Released from Rice Coleoptile Cell Walls by Protease Treatment

N-Acetylglucosamine-containing glycopeptides were released fromthe cell walls of rice coleoptiles by treatment with subtilisin.They were purified by successive treatments with different typesof proteases and by affinity chromatography using wheat germlectin- and concanavalin A-Sepharose columns. The glycopeptidefinally obtained after gel filtration contained glycine as theN-terminal amino acid and asparagine as the only amino acidcapable of linking with the sugar residue. This glycopeptidecontained only N-acetylglucosamine and mannose as sugars andcould be hydrolyzed by -mannosidase and by almond glycopeptidase.It seems to have an oligosaccharide structure, consisting of and ß-mannose and chitobiose attached to asparagine.The results indicate that this wall glycopeptide is a componentof asparagine-linked glycoprotein. ³Present address: Department of Biology, Faculty of Science,Osaka City University, Sumiyoshi-ku, Osaka 558, Japan. (Received May 22, 1985; Accepted December 10, 1985)     

Intravacuolar Spherical Bodies in Polygonum cuspidatum

The vacuoles in the epidermal cells of light-grown seedlingsof Polygonum cuspidatum were found to contain intensely pigmentedspherical bodies (anthocyanoplasts). Dark-grown seedlings containedsimilar spherical bodies that were unpigmented. The unpigmentedspherical bodies accumulated anthocyanin and turned into anthocyanoplastswhen dark-grown seedlings were irradiated. The unpigmented sphericalbodies of dark-grown seedlings were heavily stained upon treatmentof seedlings with neutral red. The absorption spectra of sphericalbodies and vacuoles showed that the contents of the sphericalbody were different from those of the vacuole. The sphericalbody was stable in darkness or at low temperature but was unstableat 25°C in the light. There was no correlation between theamount of anthocyanin and the percentage of cells that containedspherical bodies, suggesting that, in P. cuspidatum, the sphericalbody is not the main site of anthocyanin synthesis. ²Present address: Department of Applied Biology, Faculty ofTextile Science and Technology, Shinshu University, Ueda, 386Japan     

Osmotic volume change of cytoplasmic drops isolated in vitro from internodal cells of Characeae

Osmotic volume change was measured for drops of protoplasm isolatedfrom internodal cells of Chara australis in inorganic salt solutionsof various osmolalities. A drop was found to maintain a definitevolume in medium of a definite concentration in such a way thatVAN'T HOFF'S law practically holds. This indicates (1) thatthe surface membrane surrounding the isolated drop is semipermeable,and (2) that practically all the space of the protoplasmic dropis osmotically active. ¹Visiting Research Associate of the Japan Society for the Promotionof Science. Permanent address: Department of Biology, OchanomizuUniversity, Otsuka, Tokyo, Japan. (Received June 24, 1969; )     

Seasonal patterns in gonad maturation, sex ratio and size in some small, high-latitude copepods: implications for overwintering tactics

Seasonal changes in gonad maturation, sex ratio and size aredescribed for field populations of the marine calanoid copepodsPseudocalanus acuspes (Giesbrecht, 1881) and Acartia longiremisLilljeborg in Balsfjorden, northern Norway. Reproductive populationsof both species were present from March to September. Beginningin August, gonads in P.acuspes late copepodites and A.longiremisadult females switched to an undeveloped resting state. Dormancywas terminated in late winter, several weeks before the vernalbloom. Small samples of Pseudocalanus minutus (Boeck) indicatedboth an earlier induction and termination of the overwinteringphase in this species. Overwintering populations of P.acuspescopepodite stage V were dominated by males, but sex ratios evenedout at the time of spring moulting and mating. Juvenile maleswere larger than the females, except after the vernal bloomand in early summer. The findings are discussed in relationto seasonal life history tactics. ¹Present address: Department of Aquatic Biology, The NorwegianCollege of Fishery Science, University of Tromsø, Dramsveien201B, N-9037 Tromsø, Norway     

Purification and Characterization of Two Isozymes of Chlorophyllase from Mature Leaves of Chenopodium album

Chlorophyllase (Chlase) was purified from mature leaves of Chenopodiumalbum, and its enzymatic properties were investigated. Chlasewas extracted from acetone powder of C. album and purified bythe following chroma-tographic procedures: hydrophobic chromatography,Con A Sepharose, Heparin affinity chromatography, Mono Q ion-exchangechromatography, and gel-filtration. Con A Sepharose affinitychromatography and gel-filtration were the most effective stepson the purification. On Mono Q chromatography, the Chlase preparationseparated into two major and one minor fractions that exhibitedChlase activity. The two major Chlases were purified to homogeneity.Their molecular masses were estimated as 41.3 kDa and 40.2 kDaby SDS-PAGE. The optimum pH and K_m values of these two Chlaseswere similar. Their N-terminal amino acid sequences were almostidentical except for a deletion in the tenth amino acid residuein one of the Chlase; there was no homologous protein detectedby database search. ³Present address: Department of Biology and Geoscience, Facultyof Science, Shizuoka University, 836 Ohya, Shizuoka, 422 Japan.     

Synergistic Function of rolB, rolC, ORF13 and ORF14 of TL-DNA of Agrobacterium rhizogenes in Hairy Root Induction in Nicotiana tabacum

Comparison of the frequency of rooting in the tobacco leaf segmentsinoculated with Agrobacterium tumefaciens harboring variouscombinations of rolB, rolC, ORF13 and ORF14 of TL-DNA of Riplasmid (pRiHRI) revealed that the genes differ in their functionto stimulate adventitious root induction. A single gene rolBinduced roots, while rolC, ORF13 and ORF14 independently promotedthe root induction by the rolB gene. The effects of these geneson the rolB-mediated rooting were in the order of ORF13>rolCORF14. Present address: Laboratory of Phylogenetic Botany, Departmentof Biology, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba,263-8522 Japan. ² Present address: Department of Chemical and Biological Sciences,Faculty of Science, Japan Women's University, 2-8-1 Mejirodai,Bunkyo-ku, Tokyo, 112-8681 Japan.     

STUDIES ON CHLOROPHYLLASE OF CHLORELLA PROTOTHECOIDESI. ENZYMATIC PHYTYLATION OF METHYL CHLOROPHYLLIDE

1. The relation between chlorophyll content and the hydrolyticactivity of chlorophyllase in Chlorella protothecoides was examined.An increase in the activity was parallel to that in chlorophyllcontent during the development of green colouration, or greeningcourse, in the bleached cells. The activity sharply declinedand a parallel disappearance of chlorophyll was also found duringbleaching of the green cells.
2. A partially purified water-solublepreparation of chlorophyllasewas obtained by n-butanol treatmentand fractionation with coldacetone. It showed high activityand hydrolyzed 2 mg chlorophylla per hr per mg protein.
3. Forseparation and identification of the pigments concernedin thechlorophyllase reaction, a new solvent system of paperchromatographywas introduced.
4. When methyl chlorophyllide a and phytol wereincubated withthe enzyme, two products were formed. By comparisonwith theRf values of isolated pure substances, one was identifiedaschorophyll a and the other as chlorophyllide a. This enzymedid not catalyze the phytylation of free chlorophyllide a, butit had the ability to attach phytol to methyl chlorophyllidea. The final step in the biosynthesis of chlorophyll a is brieflydiscussed.

¹ Contribution No. 158 from the Department of Biology, Facultyof Science, Kyushu University. Supported in part by a grant-in-aidfor Fundamental Scientific Research from the Ministry of Education.     

黑龙江省康蝗属一新种(直翅目：蝗总科)

报道了采自黑龙江省克山县古城镇的康蝗属一新种克山康蝗Kangacriskeshanensis Renet Zheng,sp. nov、并与其近似种做了比较。