ライフサイエンスコーパス: respire

1 cy (H(2) production by nitrogenase per CO(2) respired).

2 e burst in H2O2 production as cells begin to respire.

3 tRNA enabled mto1, mto2, and mss1 strains to respire.

4 ltimately compromising the cell's ability to respire.

5 his mutant but also increases its ability to respire.

6 challenge in organisms that are obligated to respire.

7 the Delta cbp1 Delta pet127 strain does not respire.

8 ail to accumulate mature COB mRNA and cannot respire.

9 eas those that lack both CtaI and Cyd do not respire.

10 the location and rate at which marine DOC is respired.

11 on the proportion of photosynthesis that is respired.

12 which maintained the excess of COX capacity, respired.

13 9%), whereas 7% entered the root and 24% was respired.

14 e was produced, transported belowground, and respired.

15 Shewanella putrefaciens strain 200 respires a wide range of compounds as terminal electron

16 ionship between the fraction of GPP that was respired above ground (Ra /GPP) and the mean daily tempe

17 ssimilatory metal-reducing bacteria can also respire alternative electron acceptors to survive, inclu

18 ion in part by using host-derived nitrate to respire anaerobically and compete successfully with the

19 A ccmB deletion mutant was unable to respire anaerobically on any electron acceptor, yet reta

20 y inactivated ferE construct, were unable to respire anaerobically on Fe(III) or Mn(IV) yet retained

21 biX mutant in P. denitrificans was unable to respire anaerobically on nitrate, proving the role of si

22 ility of Rhodobacter sphaeroides 2.4.1(T) to respire anaerobically with the alternative electron acce

23 free-living aerobe that cannot fix nitrogen, respire anaerobically, or metabolize hydrogen.

24 Shewanella putrefaciens strain 200 respires anaerobically on a wide range of compounds as t

25 ide (TMAO), Rhodobacter sphaeroides 2.4.1(T) respires anaerobically using the molybdoenzyme DMSO redu

26 bacterial species that can obtain energy by respiring anaerobically with selenate as the terminal el

27 educed oxygen tension and is even capable of respiring anaerobically within the thickened airway mucu

28 Cells lacking mitochondrial RNase P cannot respire and accumulate lesions in their mitochondrial DN

29 inkage between the ability of yeast cells to respire and activation of glycogen synthase.

30 ctor of 4-5, accounting for their ability to respire and grow on non-fermentable carbon sources at ne

31 rown bacteria and microorganisms that do not respire and/or express haem uptake systems were resistan

32 om upland and flooded forests, which is then respired and outgassed downstream.

33 the levels of 2-hydroxyethidium in normally respiring and antimycin A-treated mitochondria and demon

34 Furthermore, C. albicans cells were respiring and had polarized membranes at least 80 min af

35 d to successfully transition rapidly between respiring and nonrespiring conditions without loss of vi

36 m despite equal amounts of ADP and ATP under respiring and nonrespiring conditions.

37 Growth of the CF-respiring and the DCM-degrading Dehalobacter populations

38 dysfunction with age was found in the lower respiring and well coupled first dorsal interosseus (43-

39 ic methanogen into the heterotrophic, oxygen-respiring, and bacteriorhodopsin-photosynthetic haloarch

40 nd complete loss of respiration in the still respiring anti-Fas-treated cells, but not in naive cells

41 These clones respired approximately 50% less than the parental mouse

42 Here, we report that CN-32 respires arsenate and that this metabolism is dependent

43 neration, either by oxidizing arsenite or by respiring arsenate.

44 ype sequence rescues the mutants' ability to respire As(V).

45 Strains that lack one oxidase respire at near-wild-type rates, whereas those that lack

46 nstrate that extraocular muscle mitochondria respire at slower rates than mitochondria from limb musc

47 Roughly one-third of the carbon respired at any temperature was fixed from the atmospher

48 gly, we found that this cell line (CRL 2613) respired at close to normal levels because of an aberran

49 Articular chondrocytes and TC28 cells respired at comparable rates.

50 sites with low soil phosphorus, smaller ants respired at higher rates than expected based on their ma

51 n overall increase in the mean age of carbon respired at higher temperatures, even correcting for pot

52 ypically be classified as 'soluble' are also respired at the cell surface.

53 ication reactions suggest that cell walls of respiring B. subtilis cells have a relatively low pH env

54 The walls of respiring B. subtilis cells were amenable to carboxylate

55 Respiring B. subtilis TUA-containing cells labelled with

56 The majority of organic carbon is respired back to carbon dioxide in the biosphere, but a

57 rated the presence of highly efficient anode-respiring bacteria (ARB) able to produce high current de

58 ong glucose fermenters, acetogens, and anode-respiring bacteria (ARB).

59 pling Fe(0) with H(2)-utilizing organohalide-respiring bacteria (i.e., Dehalococcoides mccartyi) coul

60 ropogenic organohalogens, these organohalide-respiring bacteria (OHRB) were soon found to reside in p

61 Arsenate [As(V)]-respiring bacteria affect the speciation and mobilizatio

62 in microbial fuel cells (MFC) between anode-respiring bacteria and microorganisms that use other ele

63 nd complex integral membrane enzyme found in respiring bacteria and mitochondria.

64 iter qPCR platform to identify organohalogen-respiring bacteria and populations by quantifying major

65 r biofilms and stay more active than soluble-respiring bacteria biofilms because their electron accep

66 10(3) -10(6) cells of psychrophilic nitrate-respiring bacteria g(-1) of sediment.

67 identify the presence and activity of As(V)-respiring bacteria in arsenic-contaminated iron-rich sed

68 te the population structure of organohalogen-respiring bacteria in complex environments and to identi

69 can be used to monitor sites in which As(V)-respiring bacteria may be controlling arsenic geochemist

70 riable epsilon values for other organohalide-respiring bacteria might thus be attributed to different

71 ns suggests that low numbers of organohalide respiring bacteria rather than bioavailability accounts

72 o explore the ability of native organohalide respiring bacteria to dechlorinate PCDDs, we first enric

73 Mineral-respiring bacteria use a process called extracellular el

74 Black carbon-respiring bacteria were immediately active and outcompet

75 ence intensity over time were still actively respiring bacteria, and thus, active albeit minor member

76 olically active bacteria, including arsenate-respiring bacteria, were determined by DNA stable-isotop

77 or biological dehalogenation in organohalide respiring bacteria, with substrates including polychlori

78 rvest from a culture of a tellurium-oxyanion respiring bacteria.

79 nown due to the extremely slow growth of PCB-respiring bacteria.

80 mic feature of closely related organohalogen-respiring bacteria.

81 irst documentation for a gram positive anode respiring bacterium (ARB).

82 The mineral-respiring bacterium Shewanella oneidensis uses a protein

83 ameworks can support the growth of the metal-respiring bacterium Shewanella oneidensis, specifically

84 richlorobiphenyl (PCB 23) by an organohalide-respiring bacterium, Dehalobium chlorocoercia (DF-1).

85 richlorobiphenyl (PCB 23) by an organohalide respiring bacterium, Dehalobium chlorocoercia DF-1, were

86 ctus, an obligate H2-oxidizing, chloroethene-respiring bacterium.

87 hile if turnover is slow the accumulation of respiring biomass is high and respiration depends primar

88 that if turnover is fast the accumulation of respiring biomass is low and respiration depends primari

89 es killed or infested 85% of the aboveground respiring biomass.

90 ensis strain MR-1 is required to effectively respire both soluble and insoluble forms of oxidized iro

91 resent direct radiocarbon measurements of OC respired by bacteria in freshwater aquatic systems, spec

92 when the organic matter from these blooms is respired by bacteria.

93 s into smaller, soluble monomers that can be respired by microbes.

94 mmertime warming decreased the age of carbon respired by the ecosystem due to increased proportional

95 autotrophic respiration, the fraction of GPP respired by trees is predicted to increase with warming,

96 t photosynthate, while nearly one-quarter of respired C was from a storage pool.

97 ion, R(S), the flux of microbially and plant-respired carbon dioxide (CO(2)) from the soil surface to

98 The presence of this respired carbon has been recorded by an array of paleoce

99 the depth, origin and even existence of the respired carbon pool.

100 here more than 10 y ago, and the mean age of respired carbon reflected a mixture of substrates of var

101 e suggest that the deep Pacific is a site of respired carbon storage associated with periods of decre

102 Respired carbon storage in the deep Atlantic was therefo

103 in deep ocean oxygenation and, by inference, respired carbon storage throughout the last glacial cycl

104 t the Last Glacial Maximum and its impact on respired carbon storage using radiocarbon and stable car

105 Our data suggest that respired carbon was removed from the abyssal Southern Oc

106 ociated with poor ventilation and storage of respired carbon, potentially linked to atmospheric CO2 l

107 A greater amount of respired carbon, therefore, must have been stored in the

108 oduction, decreasing the C-CO2 :C-CH4 of the respired carbon.

109 cean of a fast escape route for accumulating respired carbon.

110 hypelagic ocean are metabolically active and respiring carbon.

111 osolic soluble pyrophosphatase, we show that respiring cells arrest in S phase upon Ipp1p deficiency,

112 This suggests that in non-respiring cells electrons are transferred from NADH to a

113 Respiring cells exposed to various levels of atmospheric

114 py images revealed a thick layer of actively respiring cells of T. ferriacetica (~38 mum), which is t

115 latory activities of HSP101 were inactive in respiring cells or in cells subject to nutrient limitati

116 enriched lipids from slower-growing, healthy respiring cells relative to fast-growing, fermenting hep

117 RNA revealed two unique start sites, one for respiring cells that correlated with the RexDvH-binding

118 In respiring cells the rate of H2O2 production was approxim

119 oximately 40% of the Fe in mitochondria from respiring cells was present in respiration-related prote

120 We found that these respiring cells were unexpectedly tumorigenic, suggestin

121 ferment and provide the more slowly growing, respiring cells with ethanol.

122 o two distinct intracellular compartments in respiring cells, the mitochondrial matrix and the cytoso

123 by following the formation of carboxy-Hmp in respiring cells.

124 nthesis and growth are restricted to sulfide-respiring cells.

125 b heme is maintained in an oxidized state in respiring cells.

126 lopment of the mouse embryo and for actively respiring cells.

127 r other reductants drive Fenton chemistry in respiring cells.

128 es in metabolic flows between fermenting and respiring cells.

129 large pool of Ccp1 exits the mitochondria of respiring cells.

130 covery of distinct Dehalobacter strains that respire CF to dichloromethane (DCM) and ferment DCM to n

131 MS-1 is the first reported obligate arsenate-respiring chemoautotroph which grows by coupling arsenat

132 (Rattus norvegicus), a comparable number of respiring clones could be obtained.

133 eter suffers from largely unconstrained soil-respired CO(2) concentration (S(z)).

134 ts indicate that phototrophs are also fixing respired CO(2) from heterotrophic metabolism of the unde

135 We added measurements of carbon isotopes in respired CO(2) to constrain the age of carbon substrates

136 ve N load, suggesting more labile sources of respired CO2 .

137 le, leaf respiration (R) - the flux of plant respired CO2 from leaves to the atmosphere.

138 Subsequent (14) C dating of respired CO2 indicated that the presence of plants in sw

139 rol C, as determined by (13)C-content in the respired CO2, with higher fullerol mineralization in an

140 term incubations of marine microbial nitrate-respiring communities with isotope labeling and metageno

141 transfer of the fluids, an actively sulfate-respiring community was re-established.

142 g toxicity; however, some microorganisms can respire compounds of this redox-sensitive element to rea

143 In contrast, under respiring conditions, the mitochondrial Hsp70s Ssc1 and

144 induction or repression relative to fumarate-respiring conditions.

145 ly four to six times slower than aerobically respiring counterparts with similar cell volumes.

146 ls contained within the 10 kl of air that is respired daily.

147 feasible alternative to PCBs to isolate PCB-respiring Dehalococcoides from PCB-enriched cultures.

148 The cultivation of PCB-respiring Dehalococcoides in pure culture and the identi

149 ect of NH(4)(+) availability on organohalide-respiring Dehalococcoides mccartyi (Dhc) growth and redu

150 ue to the absence of specific vinyl chloride respiring Dehalococcoides mccartyi or to the inhibition

151 The fitness of vinyl chloride respiring Dehalococcoides mccartyi subpopulations is par

152 as an alternative electron acceptor, the PCB-respiring Dehalococcoides were boosted to a higher cell

153 sites using microbial cultures harboring TCE-respiring Dehalococcoides whose growth is cobalamin (vit

154 m a fermenting, glucose-repressed state to a respiring, derepressed state.

155 re used to obtain SECM images of immobilized respiring E. coli, illustrating the suitability of BDD U

156 Unable to respire efficiently, resistant parasites fail to complet

157 As the ability to sense, locate, and respire electrodes has applications in bioelectrochemica

158 tion, and Hg(II) coordination in aerobically respiring Escherichia coli (E. coli).

159 he ability to ferment glucose to ethanol and respire ethanol once glucose is consumed.

160 an inflamed gut is because of its ability to respire ethanolamine, which is released from host tissue

161 d from LECA after integration of this oxygen-respiring eubacterium.

162 n the cytosol and mitochondria of all oxygen-respiring eukaryotes.

163 As predicted by the model, the inability to respire evolved only in small populations of S. cerevisi

164 nfermentative, facultative anaerobe known to respire exogenous electron acceptors, generates ATP prim

165 n of conductive protein filaments or pili to respire extracellular electron acceptors such as iron ox

166 ed of mitochondrial DNA (rho0 cells) fail to respire, fail to activate mRNA for erythropoietin, glyco

167 othesis that extraocular muscle mitochondria respire faster than do mitochondria from limb muscles be

168 A nuo deletion mutant can efficiently respire formate but is deficient in alpha-ketoglutarate

169 asurements of electron transport in actively respiring Geobacter sulfurreducens wild type biofilms us

170 diheme c-type cytochrome abundant in Fe(III)-respiring Geobacter sulfurreducens, designated MacA, was

171 f Pollution Indoors and Respiratory Effects (RESPIRE) Guatemala study was a trial comparing respirato

172 acterial halophiles (Haloarchaea) are oxygen-respiring heterotrophs that derive from methanogens--str

173 the nature (i.e., age and source) of this OC respired in surface waters is largely unknown.

174 al initiation factor 2 (mIF2), are unable to respire, indicative of defective mitochondrial protein s

175 nctions of KRIPP1 and KRIPP8 in the actively respiring insect stage, but not in the mammalian stage.

176 suggest a growth penalty is associated with respiring insoluble electron acceptors at micron distanc

177 We show that the ability to respire is essential for maintaining the energy status a

178 The ability of this mutant to respire is restored by RIB3, a gene previously shown to

179 this, the interaction of ONOO- with CcOX in respiring isolated mitochondria only yielded NO* when as

180 ultaneously these two pools of superoxide in respiring isolated rat skeletal muscle mitochondria usin

181 ochondrial function and morphology in poorly respiring LM7 and 143B osteosarcoma (OS) cell lines show

182 Since these primordial times, the respiring mammalian cell has become entirely dependent o

183 Dehalobacter strain 14DCB1 are organohalide-respiring microbes of the phyla Chloroflexi and Firmicut

184 ession away from anaerobic ecosystems toward respiring microbial communities fueled by oxygenic photo

185 lectron donor within the entire organohalide-respiring microbial community.

186 reductive defluorination by an organohalide-respiring microbial community.

187 mediated by Fe(II)-rich minerals or selenate-respiring microorganisms.

188 lated the native populations of organohalide-respiring microorganisms.

189 ps, give rise to new cell bodies packed with respiring mitochondria and alpha-granules.

190 Here, we describe that respiring mitochondria are also essential for the activa

191 onditions and which lead us to conclude that respiring mitochondria are essential for the activation

192 se data provide the first demonstration that respiring mitochondria are the primary source of H(2)O(2

193 to protect cells depended on the presence of respiring mitochondria as ECV304+eNOS cells with diminis

194 eneral conclusion from these studies is that respiring mitochondria can convert external ADP to ATP a

195 reversible tyrosine nitration that occurs in respiring mitochondria during oxygen deprivation followe

196 ations in external free [Ca(2+)] in purified respiring mitochondria from rat heart to show that only

197 itions of weak intracellular Ca2+ buffering, respiring mitochondria play a central role in store-oper

198 hain, were used to demonstrate that actively respiring mitochondria play an essential role in endoper

199 Respiring mitochondria produce H(2)O(2) continuously.

200 Respiring mitochondria produce superoxide and release it

201 n the time course of matrix free [Ca(2+)] in respiring mitochondria purified from rabbit heart with a

202 orted very rapidly at 3 micromol/min.mg, and respiring mitochondria swell in the K+ salts of these ac

203 Ca(2+) is transported into respiring mitochondria via the Ca(2+) uniporter, which i

204 Second, live respiring mitochondria were stained with the membrane po

205 nsitivity of store-operated influx to InsP3, respiring mitochondria will determine whether modest lev

206 is the primary efflux pathway for Ca(2+) in respiring mitochondria, and hence plays an important rol

207 occur concurrently, were similar to those of respiring mitochondria.

208 rter is the primary Ca2+ uptake mechanism in respiring mitochondria.

209 ty to a source of reactive oxygen species in respiring mitochondria.

210 ial O(2) consumption/g) attributable to less respiring mitochondria.

211 f glyburide and 5-HD on K+ flux in isolated, respiring mitochondria.

212 n by making membrane potential recordings in respiring mitochondria.

213 al quality control, promoting maintenance of respiring mitochondrial networks through cristae stabili

214 rs from 327 mitochondrial proteins in whole, respiring murine mitochondria.

215 We identified respiring mutants from a cox18Delta strain overexpressin

216 st that a vigorous deepwater bacterial bloom respired nearly all the released methane within this tim

217 Respiring neonatal rat cerebrocortical slices were expos

218 uction, but cells of this strain could still respire nitrate anaerobically.

219 ultatively aerobic SUP05 are more active and respire nitrate when oxygen becomes available at low con

220 spirome to allow the organism to efficiently respire nitrate without the significant release of inter

221 eptomycin-treated mouse large intestine that respires nitrate.

222 e (nrfA) as a D. vulgaris nrfA mutant cannot respire nitrite but remains capable of utilizing nitrite

223 which explains the viability of populations respiring NO(2)(-) and N(2)O in a NO(3)(-)-filled ocean.

224 DOC represents 90% of the respired non-sinking organic carbon.

225 These respiring ("non-Warburg") cells were previously thought

226 iously shown to be induced in an aerobically respiring nos mutant, suggesting a potential interplay b

227 on the ability to alter the ocean interior's respired nutrient inventory.

228 three Dehalococcoides mccartyi strains that respire on commercial PCBs.

229 nella oneidensis is known for its ability to respire on extracellular electron acceptors.

230 n Shewanella putrefaciens that are unable to respire on humic substances.

231 in vivo, we find that synaptosomes prefer to respire on non-glycolytic substrates, even when glucose

232 us far, no pure culture has been reported to respire on the notorious polychlorinated biphenyls (PCBs

233 independent data from isolated mitochondria respiring on different substrates and subject to a varie

234 guanosine monophosphate (c-di-GMP) in cells respiring on nitrate than those grown aerobically (1.3 x

235 sly, we showed that in isolated mitochondria respiring on succinate, ROS generation was a hyperbolic

236 itochondria from 5-day-old sod2 null animals respiring on the complex II substrate succinate exhibite

237 iplasmic nitrate reductase deleted could not respire or assimilate nitrate and did not express nitrat

238 rankia alni ACN14a was found to be unable to respire or grow on glucose as sole carbon source.

239 tural components with regard to how much was respired or in the amount of litter biomass stabilized.

240 are no thermodynamic reasons why chlordecone-respiring or -fermenting organisms should not exist.

241 A search for chlordecone-respiring organisms and choosing between reductive versu

242 ored the expansion of aerobic ecosystems and respiring organisms, and, as a result, isotopic signatur

243 ricarboxylic acid cycle (TCA) of aerobically respiring organisms.

244 We show that strain EF1 cells respire oxygen and nitrate and that cells have higher gr

245 ns of oxygen ingress due to their ability to respire oxygen and produce a less aggressive form of sul

246 ble Fe(III), but retains the same ability to respire oxygen or fumarate as the wt.

247 t the protection is lost when the ability to respire oxygen under micro-aerophilic conditions is gene

248 tory versatility, including their ability to respire poorly soluble substrates by using enzymatic mac

249 lines containing exclusively mutated mtDNAs respire poorly, overproduce lactic acid, and have signif

250 ergistic interaction with other organohalide-respiring populations generating their metabolic electro

251 l body of the fish, detect undamaged cryptic respiring prey, such as polychaete worms.

252 10(10) to 3.9 x 10(10) moles of oxygen were respired, primarily by methanotrophs, and left behind a

253 odstream stage parasites and mitochondrially respiring procyclic stage parasites were killed.

254 ed niches for primordial Earth's first As(V)-respiring prokaryotes.

255 gh the respiratory chain in mitochondria and respiring prokaryotic cells is described by the product

256 A respiring pseudorevertant of the cox2-20 mutant was hete

257 Moreover, incubation of respiring rat liver mitochondria with [(14)C]cytidine di

258 ibutions of Fe in mitochondria isolated from respiring, respiro-fermenting, and fermenting yeast cell

259 CO2 that is used to supply energy to a large respiring root system.

260 We found that in respiring root tips, anaplerotic phosphoenolpyruvate car

261 In respiring root tips, ME was found to contribute only app

262 Depolarization in respiring Salmonella mediates intense bactericidal activ

263 e Warburg effect in comparison with actively respiring Saos2 and HOS OS cells and noncancerous osteob

264 raheme cytochrome, which in the non-arsenate-respiring Shewanella species Shewanella oneidensis strai

265 White terminal roots respire significantly more than brown ones; both possess

266 hich allows microorganisms to gain energy by respiring solid redox-active minerals, also facilitates

267 The bacterium, here designated WB3, respires soluble arsenate and couples its reduction to t

268 essed the glycogen defect in cells unable to respire, suggesting that inactivation of this enzyme is

269 ichment of sequences related to the arsenate-respiring Sulfurospirillum spp. (13) C-acetate selected

270 i.e., </= 5.5) groundwater, and organohalide-respiring Sulfurospirillum spp. are key contributors to

271 ults show that a significant fraction of the respired terrestrial OC is old (in the range of 1,000-3,

272 hat TDP-43 is much more toxic when yeast are respiring than when grown on a carbon source where respi

273 rtion of ingested nutrients and recycling or respiring the balance.

274 ndrial mutations that destroy the ability to respire (the petite phenotype) and followed the accumula

275 l-meteorite nanoscale interface of the metal respiring thermoacidophile Metallosphaera sedula.

276 The consumption of oxygen by aerobes respiring this new source of organic matter in soils wou

277 ounge chair facing an oscilloscope, and they respired through a nonbreathing valve with the inspirato

278 The supply of oxygen (O(2)) to respiring tissue, cells, and mitochondria regulates meta

279 ve evolved to maintain the carriage of O2 to respiring tissues during acute hypoxic challenge.

280 onses that facilitate unloading of oxygen to respiring tissues.

281 05 Tg hydrocarbons in the plume layers fully respired to CO(2), 0.10 +/- 0.08 Tg hydrocarbons incorpo

282 certain prokaryotes are known to grow on and respire toxic metalloids of arsenic (i.e., arsenate and

283 composed primarily of c-type cytochromes to respire under anoxic conditions a variety of compounds,

284 Interestingly, this mutant is still able to respire under cholesterol-dependent growth inhibition, s

285 Shewanella oneidensis strain MR-1 can respire using carbon electrodes and metal oxyhydroxides

286 ppreciated, many gut "anaerobes" are able to respire using oxygen as the terminal electron acceptor.

287 Mycobacteria are obligate aerobes and respire using two terminal respiratory oxidases, an aa3-

288 rial gene nad7 and functional complex I, and respires using low-affinity NADH (alternative) mitochond

289 Mutants that lacked both NADH dehydrogenases respired very slowly, as expected; however, these mutant

290 ict the accepted theory that culicine larvae respire via atmospheric gas exchange.

291 microenvironment, some cancer cells can also respire via oxidative phosphorylation.

292 dominated the iron content of fermenting and respiring vma2Delta cells, indicating that the vacuolar

293 d recovery from the continuous monitoring of respired volumes (turbine) and gas concentrations (mass

294 among-cell selection favoring cells that can respire was reduced relative to within-cell selection fa

295 pet127 mutants respire well; this phenotype implies that COB precursor

296 protein (GSU3361), which suddenly ceased to respire when biofilms reached approximately 50% of the w

297 When isolated CcOX respires with ascorbate as a reducing substrate, the con

298 defined sublocations within mitochondria of respiring yeast cells by fusing a pH-sensitive GFP to pr

299 under normoxic or hyperoxic conditions, yet respiring yeast cells have low levels of reduced YHb pig

300 Normally, actively respiring yeast cells have very low levels of the flavoh