Ultrastructure of the Acidophilic Aerobic Photosynthetic Bacterium Acidiphilium rubrum

The ultrastructure of cells of Acidiphilium rubrum, which is an acidophilic aerobic photosynthetic bacterium containing zinc-complexed bacteriochlorophyll a, was studied by electron microscopy with the rapid substitution technique. Thin-section electron microscopy indicated that any type of internal photosynthetic membranes was not present in this organism despite a relatively high content of the photopigment. The majority of cells had poly-β-hydroxybutyrate granules and electron-dense spherical bodies identified as being polyphosphate granules. When the organism was grown chemotrophically with 0.1% FeSO₄, it produced another group of electron-dense granules that were associated with the inner part of the cytoplasmic membrane. An energy-dispersive X-ray analysis showed that these membrane-bound, electron-dense granules contained iron. Received: 24 November 1999 / Accepted: 5 January 2000     

Amino acid and glucose fermentation by Treponema denticola

Summary Treponema denticola was grown in serum-containing media to which ¹⁴C-labelled compounds were added. Determinations of radioactivity in the products formed indicated that the organism fermented alanine, cysteine, glycine, serine, and glucose. Fermentation products included acetate, lactate, succinate, formate, pyruvate, ethanol, CO₂, H₂S, and NH₃. The products formed from glucose constituted a small portion of the total products. Assays of enzymatic activities in cell extracts indicated that the organism degraded glucose via the Embden-Meyerhof pathway. T. denticola possessed a coenzyme A-dependent CO₂-pyruvate exchange activity associated with a clostridial-type clastic system for pyruvate metabolism. Phosphotransacetylase and acetate kinase activities were present in cell extracts. Acetyl phosphate formation and benzyl viologen reduction were detected when cell extracts were incubated with pyruvate, serine or cysteine. The data indicate that T. denticola is an amino acid fermenter and that it possesses the enzymes needed for the fermentation of glucose. However, glucose does not serve as the primary substrate when the organism grows in media including both this carbohydrate and amino acids.     

Effect of light on Synechocystis sp. and modelling of its growth rate as a response to average irradiance

The growth rate and CO₂ biofixation rate of a photosynthetic organism depend basically on the availability of light, all other factors being optimum. In dense cultures of cyanobacteria or micro-algae intended for biomass production, incident irradiance on the reactor surface is not the same as the intensity which is received by cells, as irradiance is attenuated by cell absorption and the self-shading effect. In a well-mixed, dense culture, only the average irradiance, I _av, can be considered responsible for the photosynthetic response. In this study, the photosynthetic response of Synechocystis sp., estimated from its specific growth rate, was measured for each I _av in batch cultures irradiated with different levels of external irradiance, I _ext. The specific growth rate of Synechocystis sp. depends on I _av, in accordance with the model proposed by Muller-Feuga (J Exp Mar Biol Ecol 236:1–13, 1999). A non-linear regression analysis estimated a maximum specific growth rate of 0.108 h⁻¹, at an I _av of 930 μmol photons·m⁻²·s⁻¹. This reveals that Synechocystis sp. is a highly light-tolerant strain, suitable for outdoor cultures. Higher I _av levels caused photoinhibition in batch cultures. Parameters obtained from the Muller-Feuga model show that the minimum irradiance needed to start growth mechanisms becomes less as light availability decreases, i.e. cells become more efficient in the use of light when it is scarce. This observation suggests that choosing for low-light adaptation may be a good strategy to improve productivity in dense cultures, where light is a limiting factor.     

Infection of procaryotic and eucaryotic microorganisms withMetallogenium

To elucidate the biological characteristics ofMetallogenium, a study was undertaken into the effect of infection of such organisms unable to oxidize manganese as fungi, yeasts, and bacteria with an ultrafiltrate of this organism on the subsequent behavior of the resulting binary cultures. The infection of microorganism cultures is accompanied by (a) acquisition by the binary cultures of a persistent capacity to oxidize manganese, (b) evolution of the characteristic structures ofMetallogenium (c) inhibition of the growth of the inoculated cultures; the inhibition manifests itself by fungi losing their capacity for spore formation and pigmentation, the upsetting of cell division processes, and lysis of the cells of the infected cultures all the way to death. When a heated ultrafiltrate ofMetallogenium was used to infect microorganism cultures, no signs of infection were detected.Metallogenium may be hosted by an extremely broad range of microorganisms that are in no way allied to one another. The experimental results suggest thatMetallogenium is an organism capable of parasitizing lower eucaryotic and procaryotic microorganisms. Analysis of 134 strains of fungi isolated from freshwater bodies is indicative of possible parasitism ofMetallogenium on microorganisms in their natural habitats.     

EFFECTS OF NITROGEN SOURCES ON P-LIMITED GROWTH OF ANABAENA FLOS-AQUAE1

The effects of N₂, nitrate and ammonia as N sources were investigated in P-limited and nutrient-sufficient cultures of Anabaena flos-aquae (Lyngb.) Bréb. The maximum growth rate (μ_m) was highest at 1.34 d^?1 with ammonia, compared to 1.18 with nitrate and 0.95 d^?1 with N₂. There was no difference in P requirement between N₂ and nitrate cultures. Under P-limited conditions, the increase in cell P with growth rate (μ) was identical. With N₂ as the N source, cell-N concentrations in P-limited cells increased with μ as did cell P, and the cellular N:P ratio remained the same (14) within the range of μ examined. With nitrate, however, cell N concentrations were high and independent of n, except at a low μ. It appears that this organism fixes atmospheric N₂ only at the minimum concentration required to maintain a μ. The acetylene reduction rate increased with μ in both N_2- and nitrate-grown cells, but the rate was lower in nitrate. Under P-limitation, there was no difference in net C-fixation rate per cell between N₂ and nitrate cultures at a given μ. However, the rate per unit of chlorophyll a (chl a) was higher in N₂ than in nitrate cultures, and the rate was independent of μ with N₂ but was a linear function of nitrate supplied. The maximum C-fixation rate in nutrient sufficient cells was highest with ammonia, followed by nitrate and N₂. The cellular chl a concentration was correlated with the total cell-N concentrations regardless of H and the source of N.     

Respiration and cyanogenesis inPseudomonas aeruginosa

The respiratory ability of batch cultures ofPseudomonas aeruginosa strain 9-D2 peaks during midlog phase at 3.8 nmol O₂/min/10⁸ cells. This ability declines in late log phase, just prior to the time the culture begins to produce cyanide. The respiration of this organism is particularly sensitive to cyanide inhibition during midlog-phase growth, but is extremely resistant to this compound in stationary phase. These inhibition patterns are biphasic for each of these situations and indicate several respiratory responses to HCN. Addition of cyanide to midlog-phase cells resulted in the production of a stationary-phase type of cyanide respiration pattern in 2 h. A non-cyanideproducing mutant of this organism produced significantly less of the cyanide-resistant respiration components.     

Influence of external electron acceptors and of CO and H2 on the xylose metabolism ofBacteroides xylanolyticus X5.1

WhenBacteroides xylanolyticus X5-1 was grown on xylose in batch culture, acetate, ethanol, H₂, CO₂ and formate were the main fermentation products. CO inhibited H2 formation byB. xylanolyticus X5-1. As a result, the product formation shifted to more ethanol and formate and less acetate. Furthermore, less biomass was produced. H2 had almost no effect on the product formation from xylose. In batch cultures, dihydroxyacetone, acetone, acetoin and acetol could act as electron acceptors during xylose metabolism. The electron acceptors were reduced to their corresponding alcohols. The product formation from xylose byB. xylanolyticus X5-1 shifted to mainly acetate and CO₂, and an increased biomass yield was obtained. H₂, ethanol and formate were no longer produced. In continuous cultures not only 1,2-propanediol was formed from acetol, but also acetone. The NADP-dependent ethanol dehydrogenase that was present in xylosegrown continuous-culture cells, was repressed when the organism was grown in the presence of acetol. However, another alcohol dehydrogenase was induced for reduction of the external electron acceptor.     

RESPONSES OF FRESHWATER ALGAE TO INHIBITORY VANADIUM CONCENTRATIONS: THE ROLE OF PHOSPHORUS1

We found that species-specific differences exist among a variety of freshwater algae and cyanobacteria in the extent to which growth and photosynthesis are inhibited by vanadium. A major factor controlling the degree of inhibition by vanadium was the phosphorus state (P-sufficient vs. P-deficient) of the organisms. In P-sufficient cultures, vanadium was inhibitory when the vanadium concentration exceeded the phosphate concentration. In P-deficient cultures, the depression of photosynthesis by vanadium increased with increasing phosphorus deficiency. Our conclusion that vanadium competed with phosphate for uptake sites was supported by the following three observations: 1) the decreased influx of ³²P-PO ₄ into P-deficient cells in the presence of vanadium, 2) the amelioration of vanadium inhibition of photosynthesis by the addition of phosphate, and 3) the accumulation of vanadium by cells. At vanadium concentrations that severely inhibited growth, the cells of Scenedesmus obliquus (Turp.) Kruger were larger than normal and contained more vacuoles, lipid, and starch bodies than normal cells. Four-celled coenobia were replaced by unicells. Scenedesmus acutusf: alternans Hortobagyi cells from vanadium-inhibited cultures had 7.5 times more vanadium per cell than control cultures and contained numerous granules that did not stain for polyphosphate and may be composed of condensed vanadate molecules. The cellular P quota and turnover time of PO₄in the medium are important regulators of the extent of inhibition by vanadium.     

Physiological properties,conjugation and taxonomy ofCephaloascus fragrans Hanawa 1920 (syn:Ascocybe grovesii Wells 1954)

Summary It has been established that the type cultures ofCephaloascus fragrans Hanawa 1920,Ascocybe grovesii Wells 1954 and a culture isolated from oakwood from Japan are identical. Conjugation in this organism has been observed. The taxonomic position of this organism in theAscomycetes was discussed. If this organism is incorporated in the classification ofLodder andKreger-van Rij, it seems justified by taxonomical reasons to create a new subfamily: theCephaloascoideae.     

Transgenic Murine Dopaminergic Neurons Expressing Human Cu/Zn Superoxide Dismutase Exhibit Increased Density in Culture, but No Resistance to Methylphenylpyridinium-Induced Degeneration

Abstract: Primary dopaminergic neuronal cultures with increased superoxide dismutase (SOD) activity were established for studying the role of superoxide anion (O₂^?) in 1-methyl-4-phenylpyridinium (MPP⁺)-induced degeneration of dopamine (DA) neurons. Mean SOD activity in cultures prepared from transgenic (human) Cu/Zn SOD (hSOD1) mice was 2.46–2.60 times greater than in cultures prepared from nontransgenic control mice. After 1 and 2 weeks in culture, the mean density of DA neurons [number of tyrosine hydroxylase-immunoreactive (TH-ir) cells per visual field] was significantly higher in cultures prepared from transgenic mice compared with those prepared from nontransgenic control mice (4.55–5.63 TH-ir neurons per field in hSOD1 cultures vs. 2.66–2.8 TH-ir neurons per field in control cultures). However, uptake of [³H]DA relative to uptake of [³H]GABA was only slightly greater in hSOD1 cultures than in normal cultures (14.1 nmol of DA/100 nmol of GABA vs. 12.1 nmol of DA/100 nmol of GABA). Resistance to MPP⁺ toxicity was not significantly different from that in normal cultures when based on density of surviving TH-ir cell bodies (EC₅₀ = 0.54 µM in hSOD1 and EC₅₀ = 0.37 µM in normal cultures). A more sensitive measure of DA neuron integrity and function ([³H]DA uptake) also failed to demonstrate increased resistance of hSOD1 cultures to the toxin (EC₅₀ = 73.7 nM in hSOD1 and EC₅₀ = 86.2 nM in controls). These results do not support the hypothesis that neurotoxicity of the active metabolite of MPTP, MPP⁺, is mediated by generation of O₂^? in the cytoplasm. Nevertheless, mesencephalic cultures with increased hSOD1 activity appear to survive better than normal control cultures in the oxidatively stressful environment of cell culture incubators, and such mesencephalic cells may be useful for cell grafting studies in animal models of Parkinson's disease.     

Isolation and characterization of Dehalospirillum multivorans gen. nov., sp. nov., a tetrachloroethene-utilizing,strictly anaerobic bacterium

A strictly anaerobic bacterium dechlorinating tetrachloroethene (perchloroethylene, PCE) via trichloroethene (TCE) to cis-1,2-dichloroethene (DCE) was isolated from activated sludge with pyruvate plus PCE as energy substrates. The organism, called Dehalospirillum multivorans, is a gram-negative spirillum that does not form spores. The G+C content of the DNA was 41.5 mol%. According to 16S rRNA gene sequence analysis, D. multivorans represents a new genus and a new species belonging to the epsilon subdivision of Proteobacteria. Quinones, cytochromes b and c, and corrinoids were extracted from the cells. D. multivorans grew in defined medium with PCE and H₂ as sole energy sources and acetate as carbon source; the growth yield under these conditions was 1.4g of cell protein per mol chloride released. Alternatively to PCE, fumarate and nitrate could serve as electron acceptors; sulfate could not replace fumarate, nitrate, or PCE in this respect. In addition to H₂, the organism utilized a variety of electron donors for dechlorination (pyruvate, lactate, ethanol, formate, glycerol). Upon growth on pyruvate plus PCE, the main fermentation products formed were acetatc, lactate, DCE, and H₂. At optimal pH (7.3–7.6) and temperature (30°C), and in the presence of pyruvate (20mM) and PCE (160M), a dechlorination rate of about 50 nmol min^-1 (mg cell protein)^-1 and a doubling time of about 2.5h were obtained with growing cultures. The ability to reduce PCE to DCE appears to be constitutive under the experimental conditions applied since cultures growing in the absence of PCE for several generations immediately started dechlorination when transferred to a medium containing PCE. The organism may be useful for bioremediation of environments polluted with tetrachloroethene.Abbreviations PCE Perchloroethylene, tetrachloroethene - TCE Trichloroethene - DCE cis-1,2-Dichloroethene - CHC Chlorinated hydrocarbon     

RECIPROCAL TRANSFER OF MATERIALS BETWEEN ALGAL CELLS AND MYXOMYCETE PLASMODIA IN INTIMATE ASSOCIATION

Zabka , George G. (U. Iowa, Iowa City), and Waldo R. Lazo . Reciprocal transfer of materials between algal cells and myxomycete plasmodia in intimate association. Amer. Jour. Bot. 49 (2) : 146–148. Illus. 1962.—Pure cultures of Fuligo cinerea, a myxomycete, and Chlorella xanthella, a green alga, were separately permitted to accumulate sodium radiophosphate from an agar medium and come into full association with non-radioactive cultures of the other organism. Manipulation of such mixed cultures indicates that a Plasmodium of Fuligo cinerea and vegetative cells of Chlorella xanthella are both able to absorb radiophosphorus from a nutrient medium and transfer it to each other. It is suggested that these phenomena support the possibility of a symbiotic relationship between the alga and myxomycete in association.     

Energy requirements for microbial exopolysaccharide synthesis

Calculations indicate that at the high specific rates of exopolysaccharide synthesis obtained in continuous cultures of Xanthomonas campestris and mucoid Pseudomonas aeruginosa strains the ATP demand for this synthesis is a significant proportion of total cellular ATP demand. However, depending upon the proportion of polymer substituents more oxidised than the carbohydrate substrate, some, and in certain cases all of this energy can be provided via NAD(P)H₂ produced during exopolysaccharide synthesis. For xanthan production by X. campestris a P/O ratio of 2.2 to 2.6, depending on the content of pyruvyl substituents, would be necessary for energy generation as a direct result of xanthan synthesis to support the ATP demand for this synthesis. In sulphur-limited cultures of X. campestris, however, energy metabolism is shown to be inefficient, the organism exhibiting either a low P/O ratio or low Y _ATP. In such cultures the yield of exopolysaccharide from glucose was 0.62/g glucose compared with maximum theoretical yields of 0.81 to 0.87/g glucose for P/O ratio of 1 to 3.     

Ethanol and acetate production by <Emphasis Type="Italic">Clostridium ljungdahlii</Emphasis> and <Emphasis Type="Italic">Clostridium autoethanogenum</Emphasis> using resting cells

Combined gasification and fermentation technologies can potentially produce biofuels from renewable biomass. Gasification generates synthesis gas consisting primarily of CO, CO₂, H₂, N₂, with smaller amounts of CH₄, NO_x, O₂, C₂ compounds, ash and tars. Several anaerobic bacteria species can ferment bottled mixtures of pure synthesis gas constituents. However, there are challenges to maintaining culture viability of synthesis gas exposed cells. This study was designed to enhance culture stability and improve ethanol-to-acetate ratios using resting (non-growing) cells in synthesis gas fermentation. Resting cell states were induced in autotrophic Clostridium ljungdahlii cultures with minimal ethanol and acetate production due to low metabolic activity compared to growing cell production levels of 5.2 and 40.1 mM of ethanol and acetate. Clostridium autoethanogenum cultures were not induced into true resting states but did show improvement in total ethanol production (from 5.1 mM in growing cultures to 9.4 in one nitrogen-limited medium) as well as increased shifts in ethanol-to-acetate production ratios.     

The ferrous iron oxidation kinetics of Thiobacillus ferrooxidans in continuous cultures

The oxidation and growth kinetics of ferrous iron with Thiobacillus ferrooxidans in continuous cultures was examined at several total iron concentrations. On-line off-gas analyses of O₂ and CO₂ were used to measure the oxygen and carbon dioxide consumption rates in the culture. Off-line respiration measurements in a biological oxygen monitor (BOM) were used to measure directly the maximum specific oxygen consumption rate, qO₂,max, of cells grown in continuous culture. It was shown that these reproducibly measured values of qO₂,max vary with the dilution rate. The biomass-specific oxygen consumption rate, qO₂, is dependent on the ratio of the ferric and ferrous iron concentrations in the culture. The oxidation kinetics was accurately described with a rate equation for competitive ferric iron inhibition, using the value of qO₂,max measured in the BOM. Accordingly, only the kinetic constant Ks/K _i needed to be fitted from the measurements. A new method was introduced to determine the steady-state kinetics of a cell suspension in a batch culture that only takes a few hours. The batch culture was set up by terminating the feeding of a continuous culture at its steady state. The kinetic constant K _s/K _i determined in this batch culture agreed with the value determined in continuous cultures at various steady states. Received: 8 February 1999 / Accepted: 17 February 1999     

Monoxenic cultivation of the rotifer Brachionus calyciflorus in a defined medium

Summary Techniques are described for the initiation and maintenance of axenic cultures of Euglena gracilis strain Z and monoxenic cultures of Brachionus calyciflorus variety pala with the Euglena, using in both the same defined, buffered medium. The medium, which is inorganic—except for the citrate chelating agent, the buffer, and vitamins B₁ and B₁₂ — has been used for the axenic cultuvation of the Euglena for more than 13 months. The monoxenic Brachionus cultures, established by inoculating rotifers into Euglena cultures, have been maintained for more than 8 months. Contamination tests on the rotifer cultures were performed frequently in three different test media.Mictic females, males, and resting eggs of Brachionus were observed in the monoxenic cultures, and considerable variation in the length of the posterolateral spines was noted.The compatibility of a rotifer to a defined medium which sustains the axenic culture of its food organism is a feature of this system which is convenient, useful, and unique to date in synxenic rotifer culture work.Supported by National Science Foundation Grant No. GB 7717.     

Psychromonas antarcticus gen. nov., sp. nov., a new aerotolerant anaerobic, halophilic psychrophile isolated from pond sediment of the McMurdo Ice Shelf, Antarctica

A gram-negative, rod- to oval-shaped, aerotolerant anaerobic bacterium was isolated from an anaerobic enrichment inoculated with sediment taken from below the cyanobacterial mat of a high-salinity pond near Bratina Island on the McMurdo Ice Shelf, Antarctica. The organism was positive for terminal oxidase and catalase and was motile by means of a polar flagellum. Optimal growth of anaerobic cultures occurred at 12° C, at pH 6.5, and at an NaCl concentration of 3% (w/v). Of a variety of polysaccharides tested, only starch and glycogen supported growth. No growth was observed on cellulosic substrates and xylan, and the organism was unable to attack esculin. Monosaccharides and disaccharides, including the cyanobacterial cell-wall constituent N-acetyl glucosamine, were fermented. Per 100 mol of hexose, the following products (in mol) were formed: acetate, 60; formate, 130; ethanol, 56; lactate, 73; CO₂, 15; and butyrate, 2. Propionate, ethanol, n-propanol, n-butanol and succinate were not detectable in the culture medium (< 1 mol per 100 mol of monomer). Hydrogen was not detected in the head space (detection limit < 10^–5 atm). Growth yields in aerobic static liquid cultures were slightly higher than those in anaerobic culture, and fermentation favoured acetate at the expense of electron sink products. Growth was inhibited in aerobic shaking cultures, and the organism did not utilize nitrate or sulfate as electron acceptors. The G+C content of the DNA from the bacterium was 42.8 mol%. A phylogenetic analysis indicated that the organism is a member of the γ-subgroup of Proteobacteria, but that it is distinct from other members of this group based on the sequence of its 16S rRNA gene, mol% G+C, morphology, and physiological and biochemical characteristics. It is designated as a new genus and species; the type strain is star-1 (DSM 10704). Received: 17 June 1996 / Accepted: 13 October 1997     

Identification of a serine protease inhibitor which causes inclusion vacuole reduction and is lethal to Chlamydia trachomatis

The mechanistic details of the pathogenesis of Chlamydia, an obligate intracellular pathogen of global importance, have eluded scientists due to the scarcity of traditional molecular genetic tools to investigate this organism. Here we report a chemical biology strategy that has uncovered the first essential protease for this organism. Identification and application of a unique CtHtrA inhibitor (JO146) to cultures of Chlamydia resulted in a complete loss of viable elementary body formation. JO146 treatment during the replicative phase of development resulted in a loss of Chlamydia cell morphology, diminishing inclusion size, and ultimate loss of inclusions from the host cells. This completely prevented the formation of viable Chlamydia elementary bodies. In addition to its effect on the human Chlamydia trachomatis strain, JO146 inhibited the viability of the mouse strain, Chlamydia muridarum, both in vitro and in vivo. Thus, we report a chemical biology approach to establish an essential role for Chlamydia CtHtrA. The function of CtHtrA for Chlamydia appears to be essential for maintenance of cell morphology during replicative the phase and these findings provide proof of concept that proteases can be targeted for antimicrobial therapy for intracellular pathogens.     

The influence of the tension of oxygen on the respiration of rhizobia

Summary Cultures of Rhizobium trifolii, Rh. leguminosarum, Rh. meliloti and Rh. japonicum were grown in the Novy-Soule type of respiration apparatus and the oxygen consumed, CO ₂ produced and glucose fermented determined. From these data the respiratory quotient, the percentage of glucose used, and the carbon of the glucose used that appeared as CO₂-carbon were calculated. Since very little acids or neutral products are formed by these organisms, the carbohydrate destroyed and not appearing as CO₂ is a measure of gum production by the organisms.With Rh. trifolii, Rh. leguminosarum and Rh. meliloti, the glucose used, the rate of respiration, and to some extent the glucose that appeared as CO₂, increase with increasing p _O2. About 60 to 80 per cent of the carbon in the glucose utilized appears in the CO₂ produced. All of these cultures had an R. Q. close to unity which was independent of the p _O2. The respiratory quotient of Rh. leguminosarum was inclined to be erratic.With Rh. japonicum, the rate of respiration, total oxygen consumed, and total CO₂ produced were much lower than the values observed for the other cultures, Also the glucose used increased with decreasing p _O2. The apparatus used was not sufficiently sensitive to detect marked differences in the rate of respiration under the various tensions of oxygen with this organism, but there appeared to be a small increase in the rate of respiration with the higher tensions of oxygen.With all organisms, excellent fermentation of glucose with a high conversion into CO₂ was observed under low tensions of oxygen (five per cent or less), provided the absolute quantity of this gas was present in excess of the requirements of the organisms.Herman Frasch Foundation in Agricultural Chemistry Paper No. 66.     

Growth of Pediococcus soyae nov. sp. in Highly Concentrated Solutions of Inorganic Salts and Sugars

Pediococcus soyae nov. sp., which has an inherited salt tolerant nature, is grown in solutions of high osmotic pressure. When this strain is transferred from 0.5% salted medium to a new medium containing 18% sodium chloride, the viable counts of this organism firstly decrease from about one half to one-third of the inoculated cells, and then normal growth occurs. This indicates the occurrence of physiological adaptation at an early stage of growth.

The growth of this lactic acid bacterium is observed in concentrated solutions of various inorganic salts. The solutions containing Na⁺, K⁺, Cl^?, NO₃^? and SO₄^{– –} ions are not toxic for the organism, and the organism can grow in solutions of 133 atm. osmotic pressure, generally. However, Li⁺, Ca⁺⁺, Mg⁺⁺ and Br⁺ are, toxic for growth.

In concentrated sugar solutions, this organism also propagates well, and growth is observed in the media containing 50% glucose or 60% sucrose, osmotic pressure being 105 and 84 atm., respectively. Therefore, Pediococcus soyae nov. sp. is osmotolerant.