摘要:

ABSTRACTAtractomorpha echinatagen. et sp. nov. is described from isolates derived from zygotes present in a dry soil sample obtained from Texas. The new genus is distinguished fromSphaeropleaprimarily by its pattern of vegetative growth. WhileSphaeropleais distinctly filamentous with numerous coenocytic cells uniseriately arranged,Atractomorphagrows as individual, multinucleate, spindle‐shaped cells with sharply pointed extremities. Such cells may vary considerably in length (25–6000 μm, or more) and normally lack septa. In young, rapidly growing cultures the cells often attain lengths of 300–500 μm, but rarely exceed 1800 μm. The new species is further characterized by: (1) the regular formation of biflagellate zoospores in asexual reproduction, (2)anisogamy (occasionally oogamy) and (3) the size and ornamentation of its zygotes. Variations in vegetative morphology are discussed as are conditions for obtaining gamet

ISSN:0022-3646    

DOI:10.1111/j.0022-3646.1983.00076.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

ABSTRACTThe physiological behavior of phycoerythrin‐deficient mutants of the red seaweedGracilaria tikvahiae(Mc‐Lachlan 1979) is compared to that of their wild types. The mutants are phenotypically green while the wild types are red. Cloned scions were grown factorially at irradiances saturating and limiting to growth, and spectral distributions which were broadband (white) and narrowband (green). The green light field complements the absorptance spectrum of phycoerythrin. Experiments were performed in an outdoor continuous flow system. Physiological measurements included light‐harvesting pigment composition, instantaneous photosynthesis‐light relationships and growth. In all cases, the mutants performed as their wild type progenitors. Further, physiological responses occurring in no less than 8 days were dependent solely on irradiance (“intensity”), and were independent of spectral distribution (“color”). The data do not conform with the predictions of the theory of complementary chromatic adaptati

ISSN:0022-3646    

DOI:10.1111/j.0022-3646.1983.00086.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

ABSTRACTThe growth rate ofLaminaria saccharina (L.)Lamour. is dependent on inorganic nitrogen in culture. Growth rates were saturated between 5 and 10 μmol · L−1nitrate. The activities of ribulose‐1,5 bisphosphate carboxylase, phosphoenolpyruvate carboxykinase, mannitol‐1‐phosphate dehydrogenase, nitrate reductase and glutamine synthetase also varied with the concentration of inorganic nitrogen in the medium. All enzyme activities were lowest at 2.5 μmol · L−1nitrate (the lowest concentration used) increasing to a maximum activity between 10 and 30 μmol · L−1nitrate. Most enzyme activities followed a hyperbolic curve resembling those described by the Michaelis‐Menten equation, with different half

ISSN:0022-3646    

DOI:10.1111/j.0022-3646.1983.00092.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

ABSTRACTFreeze‐fractured thylakoids ofFucus serratusL. exhibit three types of faces with a particle density analogous to that of EFs, EFu and PF faces of green plants. However the particle size distribution is unimodal in the three types with a mean of about 8 nm. No obvious distinction between PFs and PFu faces could be detected. The absence on EFs faces of the distinct class of large particles (>13 nm) existing in green plant thylakoids implies a unique organization of pigment proteins, especially of the light‐harvesting comple

ISSN:0022-3646    

DOI:10.1111/j.0022-3646.1983.00096.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

ABSTRACTThe toxicity of Cu toThalassiosira weissflogii(Grunow) was investigated, focusing on the internal soluble pool of silicic acid. Silicic acid uptake and growth rates were found to be functions of both the cupric ion activity and the concentration of silicic acid in the growth medium. The soluble pool of Si per cell depended on the balance between the uptake rate and the division rate. The soluble pool in non‐dividing cultures reflected simply the uptake rate (and inhibition by copper of the uptake rate), but in dividing cultures the soluble pools had complex patterns with time depending on uptake rates and timing of division. Intracellular soluble pools of silicic acid are a good indicator for the relative inhibition of uptake and growth processe

ISSN:0022-3646    

DOI:10.1111/j.0022-3646.1983.00101.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

ABSTRACTA new coccoid rhodophytan species is described and compared with other species in the genusRhodella.Thylakoids in the pyrenoid characterize the new species and indicate a closer relationships ofRhodellatoPorphyridiumthan was previously indicated.

ISSN:0022-3646    

DOI:10.1111/j.0022-3646.1983.00104.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

ABSTRACTWashed cells ofDunaliella tertiolectaButcher became immobile and agglutinated upon exposure to 100–400 μ/mL lectins in NaCl solution. The agglutinations were strongest withLimulus polyphemusagglutinin and wheat‐germ agglutinin, moderate with soybean agglutinin and weakest with Concanavalin A. All lectin‐induced agglutinations were inhibited or mitigated by the simultaneous presence of specific lectin‐binding sugars. The differential sensitivity of the alga to these lectins suggested that sialic acid and/or N‐acetyl‐D‐glucosamine might be the predominant lectin‐receptor sugars in the algal surface coat, with N‐acetyl‐D‐galactosamine likely present as a lesser component. In the absence of lectins, the divalent cations Mg2+, Ca2+or Mn2+also caused agglutination, but this process required an alkaline pH of at least ca. 8.6–8.9. Such cation‐induced agglutination was reversibly inhibited by the cation complexing agent EDTA as well as by lowering the pH below 8.0. SEM observations of the agglutinations revealed random flagellar attachments as well as direct body contact

ISSN:0022-3646    

DOI:10.1111/j.0022-3646.1983.00112.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

ABSTRACTThe small and ill‐known tropical chlorophyte,Brybesia johannaeWeber‐van Bosse, is redescribed on the basis of living material from the coral reef of Curacao, Netherlands Antilles. Additional records are given from the Canary Islands. One species,B. johannae,is recognized (including,B. cylindrocarpaHowe 1920), and this probably has a wide Atlantic and Indo‐Pacific tropical distribution.Bryobesiais not related toBryopsisandDerbesia (Caulerpales),but belongs to theCladophorales.It appears to be a rudimentaryClado

ISSN:0022-3646    

DOI:10.1111/j.0022-3646.1983.00116.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

ABSTRACTA quantitative accounting of the solids in the sieve tube sap fromMacrocystis pyrifera (L.)e. Ag. was performed. The major organic compounds (mannitol, amino acids, and protein) and inorganic cations (K+, Na+, Mg2+and Ca2+) were present near previously reported levels. The anions, until now unreported (except for iodide), included chloride as the major inorganic ion, bromide, phosphate, nitrate, and bicarbonate as the major inorganic carbon species. Sulfate and ammonium were below the detection limits of 1.5 ppm and 2 ppm, respectively. The elements B and As were also present although their speciation was not determined.

ISSN:0022-3646    

DOI:10.1111/j.0022-3646.1983.00118.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

ISSN:0022-3646    

DOI:10.1111/j.0022-3646.1983.00121.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY