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1.
《Biochimica et Biophysica Acta.Protein Structure》1978,532(2):315-326
Cancer magister hemocyanin oxidized by H2O2 (Felsenfeld, G.F. and Printz, M.P. (1959) J. Am. Chem. Soc. 81, 6259–6264) contained 80–95% cupric copper, small amounts of EPR-detectable Cu(II), and native hemocyanin. The small amounts of EPR-detectable Cu(II) showed a signal characteristic of mononuclear Cu(II) in the region of g = 2 between 233°K and 10°K, with normal Curie behavior, and no Δm = 2 signal. Magnetic susceptibility measurements show the methemocyanin to be diamagnetic over the temperature range 1.5–77°K. It had an optical absorption maximum at 680 nm, ϵ = 60 ± 7 MCu−1 · cm−1 at 25°C, and at 327 nm (ϵ = 3 · 102 MCu−1 · cm−1), 360 nm, 420 nm, and 680 nm at 77°K. CD bands were observed at 340, 400–450, and 650 nm (very broad). Methemocyanin was not reduced to O2-binding cuprous hemocyanin by dithionite, hydroxylamine, ascorbate, ferrocyanide, H2O2, or superoxide. Based upon the normal Curie behavior of the small EPR-detectable signal, the absence of paramagnetism, and some similarities of optical spectra between methemocyanin and oxyhemocyanin, we conclude that the diagmagnetic Cu(II) of this methemocyanin occurs in spin-coupled binuclear Cu(II) clusters having a configuration related to the binuclear Cu(II) cluster in oxyhemocyanin; but that inability of methemocyanin to undergo reductive reactivation, and the low molecular extinction coefficients of the optical absorption bands indicate that some chemical or steric alteration, perhaps peroxidatic in nature, takes place during its formation. 相似文献
2.
Spinach plastocyanin was converted into the apoprotein. CuSO4 and oxidized Cu(II)- thionein reacted with the apoprotein to Cu(II) plastocyanin. Cu(I) transfer from Cu(I)0-thionein was only 15%. The structural analogue of the copper thiolate chromophore [Cu(I)(thiourea)3]Cl as well as [Cu(CH3CN)4]ClO4 successfully formed the Cu(I)- holoprotein. Characteristic circular dichroism bands at θ284 (?5300 deg·cm2·dmol?1 and θ310 (+3300 deg·cm2·dmol?1) were seen. Upon oxidation with ferricyanide and dialysis against phosphate buffer the correct Cu(II) binding into the active centre of Cu(II) plastocyanin was confirmed by EPR-measurements. The use of [Cu(I)(thiourea)3] Cl as a convenient Cu(I) source for reconstitution studies on copper proteins is highly recommended. 相似文献
3.
Extraction of whole lobes of normal rat liver with dimethyl sulphoxide (DMSO) under N2 gives extracts which contain 5—10 μmol/l·O?2 (50-100 nmol·O?2 per 10 ml extract per 4 g liver; 1.25-2.50 nmol·O?2 per millilitre per gram liver). Evidence for ·O?2 in the extracts is given by: (1) electron spin resonance signals (ESR), (2) differential pulse polarography (DPP), (3) chemiluminescence (CL), and (4) nitroblue tetrazolium reduction (NBT). All tests yield results identical with those obtained with authentic ·O?2. Extraction of ·O?2 is enhanced by tetrabutyl ammonium ion, and is maximal at 1-3 min. These results raise the possibility that substantial amounts of ·O?2 are normally sequestered in protective membranous sites in vivo. 相似文献
4.
In three experiments, each with three species of newly transformed juvenile fishes, the immediate mortality was determined after electrical exposure to 60 Hz pulsed DC in waters of different conductivity (Cw). With a constant applied power density (Da; 1·0–4·9 mW cm?3 depending on species) over a range of Cw(10–1020 μS cm?1), the results predicted that the highest fish mortality would occur at Cw of 65 μS cm?1 for bluegill Lepomis macrochirus, 74 μS cm?1 for largemouth bass Micropterus salmoides and at 140–175 μS cm?1 for channel catfish Ictalurus punctatus. In experiment 2, the voltage gradient (E) was maintained constant (2·5–8·0 peak V cm?1 depending on species) over the same range of Cw, and fish mortality increased with current density (J) or Da, which are directly related to Cw. In experiment 3, fish mortality did not differ when peak E(3 or 8 V cm?1 depending on species) and mean J(0·09 or 0·24 mA cm?2 depending on species) were held constant by changing pulse width in waters with different Cw(99, 165 or 495 μS cm?1). Fish mortality in this experiment was not significantly related to peak or mean transferred power density, and the ‘power transfer theory for electrofishing’ was not useful for predicting electrofishing mortality. Overall, the results of the present study indicated that mortality caused by exposure to electricity can be predicted more accurately with the variables peak E and mean J than with models requiring determination of effective conductivity of the fish. 相似文献
5.
In the past decades, it has become clear that superoxide radical (O2 ·?) can be generated from photosystem II (PSII) during photosynthesis. Depending on the extent of its accumulation, O2 ·? plays an important role in plant physiology and pathology. The photoinhibition/repair cycle is a typical process in PSII which is mainly responsible for the survival of plants under the photoinihibition condition. It is therefore of significant importance to determine O2 ·? production in this cycle, and then explore how O2 ·? is controlled by PSII within a normal physiological level. With this in mind, we herein investigate the variation of the O2 ·? levels in PSII under Mn-depleted and photoactivated conditions mimicking the photoinhibition/repair cycle in vitro. The effect of intrinsic SOD-like component on the O2 ·? levels was also studied. Results show that PSII has the ability to regulate the O2 ·? levels in these two processes by simultaneously modulating the O2 ·? generation activity and intrinsic SOD-like activity. This finding could shed new lights on the photoprotective property of PSII against O2 ·? and other reactive oxygen species. 相似文献
6.
Five-day-old etiolated barley plumules contain the C-glucosylflavones saponarin, lutonarin, and lutonarin 3′-methyl ether. When harvested 24 hr after illumination, increased flavonoid levels were essentially linear with increased energies of monochromatic light at seven wavelengths between 450 and 750 nm. Action spectra for saponarin and for a mixture of lutonarin and its 3′-methyl ether were determined between 380 and 760 nm at 6.6 kerg·cm?2. The saponarin action spectrum showed distinct peaks at 620 and at 660 nm. These two peaks were similar in their photoreversibility when followed by either 6·6 or 34 kerg·cm?2 of far-red light. Phytochrome is apparently the photoreceptor for the saponarin action spectrum. Lutonarin and its 3′-methyl ether showed peaks at 520 580, 620 and near 660 nm. The 660 nm peak was not photoreversible by 6·6 kerg·cm?1, but was by 34 kerg·cm?2, of far-red light. Phytochrome and protochlorophyll are the likely photoreceptors for these 3′-substituted flavonoids. 相似文献
7.
Teruo Ogawa 《BBA》1982,681(1):103-109
Illumination of leaves of Vicia faba L. provoked oscillations in the rates of CO2 uptake and O2 evolution. The oscillations were marked under anaerobic conditions, but were absent at 20% O2. The minimum CO2 concentration required for the appearance of oscillations was 600 μl · l?1. The higher the CO2 concentration, the stronger the oscillations. The effect of CO2 concentration was saturated at 1000 μl CO2 · l?1. The period of the oscillations was 5–6 min at a light intensity of 80 nE · cm?2 · s?1 and became longer on lowering of the intensity. No oscillations appeared at intensities below 12 nE · cm?2 · s?1. Oscillations could also be generated by increasing the CO2 concentration in the atmosphere during strong illumination under anaerobic conditions. The chlorophyl a fluorescence yield showed oscillations, similar in shape and frequency to those of photosynthesis, after such an environmental change. Oscillations were also observed in photosynthesis of other C3 plants, Lycopersicon esulentum Mill and Glycine max Merrill, under the same conditions as those required for V. faba, but were absent for the C4 plants, Zea mays and Amaranthus retroflexus L. 相似文献
8.
Photosynthesis, Photorespiration and Respiration of Detached Spruce Twigs as Influenced by Oxygen Concentration and Light Intensity 总被引:1,自引:0,他引:1
J. Poskuta 《Physiologia plantarum》1968,21(5):1129-1136
The effects of oxygen concentration and light intensity on the rates of apparent photosynthesis, true photosynthesis, photorespiration and dark respiration of detached spruce twigs were determined by means of an infra-red carbon dioxide analyzer (IRCA). A closed circuit system IRCA was filled with either 1 per cent of oxygen in nitrogen, air (21 % O2) or pure oxygen (100 % O2). Two light intensities 30 × 103 erg · cm ?2· s?1 and 120 × 103 erg · cm?2· s?1 were applied. It has been found that the inhibitory effect of high concentration of oxygen on the apparent photosynthesis was mainly a result of a stimulation of the rate of CO2 production in light (photorespiration). In the atmosphere of 100 % O2, photorespiration accounts for 66–80 per cent of total CO2 uptake (true photosynthesis). Owing to a strong acceleration of photorespiration by high oxygen concentrations, the rate of true photosynthesis calculated as the sum of apparent photosynthesis and photorespiration was by several times less inhibited by oxygen than the rate of apparent photosynthesis. The rates of dark respiration were essentially unaffected by the oxygen concentrations used in the experiments. An increase in the intensity of light from 30 × 103 erg · cm?3· s?1 to 120 · 103 erg · cm?2· s?1 enhanced the rate of photorespiration in the atmospheres of 21 and 100 % oxygen but not in 1 % O2. The rate of apparent photosynthesis, however, was little affected by light intensity in an atmosphere of 1 % oxygen. 相似文献
9.
The possible time- and/or light-dependent decomposition of the purple Cu(I), Cu(II)-complex of D-penicillamine (Cu(II)6Cu(I)8(D-penicillamine)12Cl)5? was examined. Superoxide dismutase activity of the freshly prepared complex was assayed using the nitroblue tetrazolium assay. The formazan colour formation was inhibited by 50% in the presence of approximately 500 μM copper. Ageing of the copper complex, especially in the light, resulted in a marked increase of EDTA-sensitive activity. Upon gel chromatography of the aged samples the original low inhibitory activity was restored. All EDTA-sensitive inhibitory activity was found in a clearly separated low Mr copper-containing fraction. Aerobic irradiation with a tungsten lamp at 30 °C accelerated the decomposition of (Cu(II)6Cu(I)8(D-penicillamine)12Cl)5?. ?Cu518 = 1800 M?1 cm?1 dropped to ?Cu640 = 60 M?1 cm?1. The photochemical conversion of (Cu(II)6? Cu(I)8(D-penicillamine)12Cl)5? was complete within 48 h. Due to the identical electronic absorption profile of both, the decomposition product and Cu(II) D-penicillamine disulphide the latter complex was assigned to be the unknown low Mr copper-compound. Circular dichroism and electron paramagnetic resonance measurements support this conclusion. 相似文献
10.
A study was made with a modulated oxygen electrode of the effect of variations of oxygen concentration on photosynthetic oxygen evolution from algal cells. When Chlorella vulgaris is examined with a modulated 650 nm light at 22°C, both the oxygen yield and the phase lag between the modulated oxygen signal and the light modulations have virtually constant values between 800 and 120 ergs · cm?1 · s?1 if the bathing medium is in equilibrium with the air. Similar results are obtained at 32°C between 1600 and 120 ergs · cm?2 · s?1. Under anerobic conditions both the oxygen yield and the phase lag decrease if the light intensity is lowered below about 500 ergs · cm?2 · s?1 at 22°C or about 1000 ergs · cm?2 · s?1 at 32°C. A modulated 706 nm beam also gives rise to these phenomena but only at significantly lower rates of oxygen evolution. The cells of Anacystis nidulans and Porphyridium cruentum appear to react in the same way to anaerobic conditions as C. vulgaris. An examination of possible mechanisms to explain these results was performed using a computer simulation of photosynthetic electron transport. The simulation suggests that a backflow of electrons from a redox pool between the Photosystems to the rate-limiting reaction between Photosystem II and the water-splitting act can cause a decrease in oxygen yield and phase lag. If the pool between the Photosystems is in a very reduced state a significant cyclic flow is expected, whereas if the pool is largely oxidized little or no cyclic flow should occur. It is shown that the effects of 706 nm illumination and removal of oxygen can be interpreted in accordance with these proposals. Since a partial inhibition of oxygen evolution by 3-(3.4-dichlorophenyl)-1,1-dimethylurea (10?8 M) magnifies the decreases in oxygen yield and phase lag, it is proposed that the pool which cycles back electrons is in front of the site of 3-(3,4-dichlorophenyl)-1,1-dimethylurea inhibition and is probably the initial electron acceptor pool after Photosystem II. 相似文献
11.
Ventilatory and behavioural responses of the marbled sole Pseudopleuronectes yokohamae to progressive hypoxia
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This study identified ventilatory and behavioural responses in the marbled sole Pseudopleuronectes yokohamae under experimentally induced progressive decreases in dissolved oxygen (DO) levels. Ventilation frequency showed an increase with decreasing DO levels from normoxia to 2·75 mg O2 l?1, followed by a decrease in ventilation frequency at decreased DO levels from 2·00 to 0·75 mg O2 l?1. At DO levels below 2·00 mg l?1, behaviours at the bottom were suppressed, whereas avoidance behaviours increased. A decrease in avoidance behaviours was observed from 1·00 to 0·75 mg O2 l?1. Upside‐down reversal and incapacitation at DO levels of 1·00–0·75 mg O2 l?1 suggested that sublethal effects on P. yokohamae were induced. The responses observed before the sublethal DO level could be interpreted as an effort to maintain oxygen uptake, reduce routine activities and facilitate avoidance. The observed DO level thresholds that induce behavioural responses, in addition to sublethal effects, indicate hypoxia‐tolerance that is important for understanding the effects of hypoxia on coastal ecosystems. 相似文献
12.
《African Journal of Aquatic Science》2013,38(2):305-311
The median lethal copper (Cu) concentration (96 hr-LC50) values for acute Cu toxicity for Tilapia sparrmanii (live mass: 30 ± 8g) in Mooi River hard water of dolomitic origin at 20 °C, pH 7.9, was 68.1 μmol l?1. At this 96 hr-LC50 value the specific oxygen consumption rate (∈ O2) decreased by 44.2 (± 2.1) % from a non-exposed value of 6.6 (±0.32) mmol O2 kg?1 hr?1 to 3.63 (±0.23) mmol O2 kg ?1 hr?1. At 46.4 μmol Cu l?1, 100% of the exposed T. sparrmanii were still alive after 96 hours, but the ∈ O2 decreased by a mean value of 1.65 (± 0.16) mmol O2 kg?1 fish hr?1 or 25% (± 2.4). Contrary to Pb and Cd, Cu as CuCl2 2H2O was not precipitated in hard water four days after it was dissolved. Thus T. sparrmanii and other cichlids are shown to be more than an order of magnitude more resistant to Cu as a toxicant than most salmonids. 相似文献
13.
Swimming speed, angular correlation and expected displacement were measured in juvenile summer flounder Paralichthys dentatus acclimated to either oxygen saturation (c. 7·8 mg O2 l?1; saturation‐acclimated fish) or diel‐cycling hypoxia (cycling between 11·0 and 2·0 mg O2 l?1) for 10 days and subsequently exposed to more severe diel‐cycling hypoxia (cycling between 7·0 and 0·4 mg O2 l?1). Saturation‐acclimated P. dentatus exhibited an active response to declining dissolved oxygen (DO) by increasing swimming speed, angular correlation and expected displacement to peak levels at 1·4 mg O2 l?1 that were 3·5, 5·5 and 4·2 fold, respectively, greater than those at DO saturation. Diel‐cycling hypoxia‐acclimated P. dentatus also exhibited an active response to declining DO, although it was relatively less pronounced. Diel‐cycling hypoxia‐acclimated P. dentatus swimming speed, however, still doubled as DO decreased from 7·0 to 2·8 mg O2 l?1. Diel‐cycling hypoxia‐acclimated P. dentatus did not recover as well from low DO exposure as did saturation‐acclimated fish. This was reflected in their relatively more random swimming (low angular correlation between successive moves) and poor maintenance of rank order between individuals during the recovery phase. Even saturation‐acclimated P. dentatus did not resume swimming at speeds observed at saturation until DO was 4·2 mg O2 l?1. Paralichthys dentatus were very sensitive to decreasing DO, even at DO levels that were not lethal or growth limiting. This sensitivity and their poor recovery may preclude juvenile P. dentatus from using highly productive nursery habitats affected by diel‐cycling hypoxia. 相似文献
14.
Uptake rates of dissolved inorganic phosphorus and dissolved inorganic nitrogen under unsaturated and saturated conditions were studied in young sporophytes of the seaweeds Saccharina latissima and Laminaria digitata (Phaeophyceae) using a “pulse‐and‐chase” assay under fully controlled laboratory conditions. In a subsequent second “pulse‐and‐chase” assay, internal storage capacity (ISC) was calculated based on VM and the parameter for photosynthetic efficiency Fv/Fm. Sporophytes of S. latissima showed a VS of 0.80 ± 0.03 μmol · cm?2 · d?1 and a VM of 0.30 ± 0.09 μmol · cm?2 · d?1 for dissolved inorganic phosphate (DIP), whereas VS for DIN was 11.26 ± 0.56 μmol · cm?2 · d?1 and VM was 3.94 ± 0.67 μmol · cm?2 · d?1. In L. digitata, uptake kinetics for DIP and DIN were substantially lower: VS for DIP did not exceed 0.38 ± 0.03 μmol · cm?2 · d?1 while VM for DIP was 0.22 ± 0.01 μmol · cm?2 · d?1. VS for DIN was 3.92 ± 0.08 μmol · cm?2 · d?1 and the VM for DIN was 1.81 ± 0.38 μmol · cm?2 · d?1. Accordingly, S. latissima exhibited a larger ISC for DIP (27 μmol · cm?2) than L. digitata (10 μmol · cm?2), and was able to maintain high growth rates for a longer period under limiting DIP conditions. Our standardized data add to the physiological understanding of S. latissima and L. digitata, thus helping to identify potential locations for their cultivation. This could further contribute to the development and modification of applications in a bio‐based economy, for example, in evaluating the potential for bioremediation in integrated multitrophic aquacultures that produce biomass simultaneously for use in the food, feed, and energy industries. 相似文献
15.
The ultraviolet absorption, linear dichroism, circular dichroism, and oriented circular dichroism of collagen are reported and the spectra are resolved into a self-consistent set of bands in accord with exciton theory. The parallel band at 200 nm has 40% of the π → π* intensity; the perpendicular band is placed at 189 nm yielding a splitting of 2700 cm?1. The circular dichroism is resolved into two Gaussians at λ∥ and λτ (rotational strengths +14 × 10?40 and ?32 × 10?40 esu2. cm2) plus a large non-Gaussian (“helix”) band with ampplitude ?25,000° at 201 nm. These data appear to be in reasonably good accord with recent calculations. Measurements of the absorption, linear dichroism and circular dichroism of polyproline I and II are also reported and are resolved into their component bands. Polyproline I is in good accord with exciton theory, whereas polyproline II remains unsatisfactory. 相似文献
16.
Ling Li Shuang Fang Lim Alexander Puretzky Robert Riehn Hans D. Hallen 《Biophysical journal》2018,114(11):2498-2506
We show that DNA carrying 5-methylcytosine modifications or methylated DNA (m-DNA) can be distinguished from DNA with unmodified cytosine by Raman spectroscopy enhanced by both a bowtie nanoantenna and excitation resonance. In particular, m-DNA can be identified by a peak near 1000 cm?1 and changes in the Raman peaks in the 1200–1700 cm?1 band that are enhanced by the ring-absorption resonance. The identification is robust to the use of resonance Raman and nanoantenna excitation used to obtain significant signal improvement. The primary differences are three additional Raman peaks with methylation at 1014, 1239, and 1639 cm?1 and spectral intensity inversion at 1324 (C5=C6) and 1473 cm?1 (C4=N3) in m-DNA compared to that of DNA with unmodified cytosine. We attribute this to the proximity of the methyl group to the antenna, which brings the (C5=C6) mode closer to experiencing a stronger near-field enhancement. We also show distinct Raman spectral features attributed to the transition of DNA from a hydrated state, when dissolved, to a dried/denatured state. We observe a general broadening of the larger lines and a transfer of spectral weight from the ~1470 cm?1 vibration to the two higher-energy lines of the dried m-DNA solution. We attribute the new spectral characteristics to DNA softening under high salt conditions and find that the m-DNA is still distinguishable via the ~1000 cm?1 peak and distribution of the signal in the 1200–1700 cm?1 band. The nanoantenna gain exceeds 20,000, whereas the real signal ratio is much less because of a low average enhanced region occupancy even with these relatively high DNA concentrations. It is improved when fixed DNA in a salt crystal lies near the nanoantenna. The Raman resonance gain profile is consistent with A-term expectations, and the resonance is found at ~259 nm excitation wavelength. 相似文献
17.
Wolf Bors Manfred Saran Christa Michel 《Biochimica et Biophysica Acta (BBA)/General Subjects》1979,582(3):537-542
Transient spectra and kinetic data of Tiron (1,2-dihydroxybenzene-3,5-disulphonic acid) are reported, obtained after pulse-radiolytic oxidation by hydroxyl radicals (°OH), superoxide anions (O2?) or a combination of both oxygen radicals. The rate constant with °OH radicals was determined at 1.0·109 M?1·s?1. Contrary to a previous report (Greenstock, C.L. and Miller, R.W. (1975) Biochim. Biophys. Acta 396, 11–16), the rate constant with O2? of 1.0·107 M?1·s?1 is lower by one order of magnitude; also the semiquinone absorbs at 300 nm rather than at 400 nm. The ratio of the rate constants with °OH and O2? of 100 again demonstrates that any oxidation reaction by the latter radical is unspecific due to the more efficient reaction of °OH radicals, leading to the same products with catechol compounds. 相似文献
18.
A novel environmentally friendly octahedrally coordinated 2D polymeric complexes bis(1,5-diaminotetrazole) -dichlorozinc(II) (Zn(DAT)2Cl2) was first designed based on the the crystal data of bis(1,5-diaminotetrazole)- dichlorocopper(II) (Cu(DAT)2Cl2). Density functional theory (DFT) was used to predict the optimized geometries at TPSSTPSS/6-311G(d, p) level. Densities and detonation properties were evaluated using the electron cloud enclosed volume and VLW equation of state (VLW EOS), respectively. Calculation results show that the density of Zn(DAT)2Cl2 (2.117 g?·?cm?1) is a bit more than that of Cu(DAT)2Cl2 (2.106 g?·?cm?1). The calculated high positive heat of formation (HOF) predicts that the stabilities of the title compounds decrease in the order Zn(DAT)2Cl2 > Cu(DAT)2Cl2, which agrees with the result of bond dissociation energies (BDE). Even though they have the same molecule structures, their first scission steps are different. Furthermore, the title two compounds show good detonation velocities and pressures compared with that of bis-(5-nitro-2H-tetrazolato-N 2) tetraamminecobalt(III) perchlorates (BNCP), and they are potential candidates for high-energy-density materials (HEDM). 相似文献
19.
K Nagami 《Biochemical and biophysical research communications》1973,51(2):364-369
The fast reaction technique of pulse radiolysis was used to produce free radicals in aqueous solution from alcohols, deoxyribose, cytosine, uracil, thymine, dihydrothymine and histidine. The electron transfer reactions from these radicals to p-benzoquinone was observed from the formation kinetics of the semiquinone anion ·BQ? at 430 nm and the efficiency was found to be as high as 90% or more, with k~5×109 M?1sec?1. In acid or neutral solutions in the presence of oxygen the peroxy radicals ·O2RH formed do not essentially transfer an electron to BQ, and the efficiency is <10%. The significance of these results in the fixation of radiation damage in photobiology and radiation biology are indicated. The reactions of the superoxide ·O2? radical with BQ are also presented and discussed. 相似文献
20.
Dark respiration of the stipe of Ecklonia cava (Laminariales, Phaeophyta) in relation to temperature
Yukihiko Serisawa Yasutsugu Yokohama Yusho Aruga Jiro Tanaka 《Phycological Research》2004,52(2):174-179
Sporophytes of Ecklonia cava Kjellman (Laminariales, Phaeophyta) with a stipe length of 22–102 cm were collected at 6–9 m depth in Nabeta Bay, Shimoda, central Japan by scuba diving in February (winter) and in August (summer) 1998. Dark respiration of the intact stipe of E. cava was measured at various water temperatures ranging from 15 to 27.5°C in winter and 15–30°C in summer in a closed system by using a dissolved oxygen meter. The stipe respiration was compared on whole stipe, length, surface area, volume, wet weight and dry weight bases. On each basis, the stipe respiration always increased with a rise in water temperature within the temperature range investigated. The stipes showed similar respiration rates on each basis of length, surface area, volume, wet weight and dry weight at each temperature, irrespective of the stipe length. The mean respiration rates in winter (at 15–27.5°C) were: length, 16.7–32.5 μL O2 cm?1 h?1; surface area, 3.2–6.2 μL O2 cm?2 h?1; volume, 7.6–15.0 μL O2 cm?3 h?1; wet weight, 6.2–12.2 μL O2 g (wet weight)?1 h?1; and dry weight, 43.8–88.0 μL O2 g (dry weight)?1 h?1. Those for summer (at 15–30°C) were: length, 17.1–32.0 μL O2 cm?1 h?1; surface area, 3.6–6.8 μL O2 cm?2 h?1; volume, 9.7–18.7 μL O2 cm?3 h?1; wet weight, 7.6–14.6 μL O2 g (wet weight)?1 h?1; and dry weight, 49.4–95.8 μL O2 g (dry weight)?1 h?1. This is the first report of the intact stipe respiration of E. cava at various temperatures. 相似文献