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PubMedDate not supplied

[Bacterial flora of the conjunctival sac of the horse].

The AA. report the results of taxonomic research conducted on the conjunctival sac of 59 horses for identification of the present bacterial flora. In the controlled animals, it was observed, at the level of the considered niche, a community constituted of normal bacterial populations, but not autochtonous in the significance they attributed from DUBOS et al., relative to the characterization of the indigenous microbiota of the intestine. The isolated normal bacterial flora seems to be constituted of: Micrococcus (subgroup 6 of Baird-Parker, M. luteus, Micrococcus spp.) isolated in 49,15% of the samples; Staphylococcus aureus and St. epidermidis (18,64%); Moraxella osloensis, M. phenylpiruvica, M. equi and Moraxella spp. (11,86%); Bacillus cereus (11,86%); Neisseria catarrhalis (8,47%); Streptococcus equi and Str. zooepidemicus (6,77%); Corynebacterium spp. (6,77%) and Acinetobacter lwoffi (5,08%). The AA. have found, besides, a particular group of bacteria of uncertain classification, attributed to the coryneforms and found in 30,50% of the examined horses. So-called transient bacteria taxa have been considered are Streptomyces spp., isolated in the 10,16% of the controlled subjects, Aerococcus viridans and Bacillus spp. found in only one equine.

Animals↗
PubMed1994

[Bacteria-reducing properties of copper-containing and non-copper-containing materials. II. Relationship between microbiocide effect of copper-containing materials and copper ion concentration after contamination with moist and dry hands].

The bactericide quality of different materials containing copper (copper, brass, brass-sheet) was tested and particularly the effect of humidity and copper-concentration was examined. In first examinations (I. communication) (19) the materials were contaminated by hands, which were dipped into a suspension of different microorganisms (Micrococcus luteus, Staphylococcus aureus, Enterococcus faecium, Escherichia coli, Enterobacter cloacae, Pseudomonas aeruginosa). The survival rate of the microorganisms on the surfaces was determined after defined exposure times (0, 5, 30, 60, 120 min). The following ways of contaminating the test materials were chosen: single contamination with wet hands, repeated contamination with wet and dry hands. In this examination the results were tested for statistical significance and in parallel experiments the copper-concentration on the surfaces of the materials was determined. Materials containing copper contaminated with wet hands show a significant bactericide effect after an exposure time of 120 min. The bactericide effect on Micrococcus luteus and Pseudomonas aeruginosa is inhibited after contamination with dry hands. This results can not be explained by a different copper-concentration on the surfaces of the materials, because a statistically significant difference of copper-ion concentrations between contamination with wet and dry hands could not be obtained.

Bacteria↗
PubMed1976

[Persistance of penicillin residues in the calf organism after parenteral therapeutical administration of the preparation penicillin G, procaine inj ad usum vet].

By means of two biological diffusion methods a penicillin content in various calf tissues was determined. For the injections PROKAIN Penicillin G Spofa, inj. adusum vet., was used in a single dose of 25 000 i. u. kg-1 body mass. For the tests three collection strains -- B. subtilis (ATCC 6633), Sarcina lutea (ATCC 9341), and Micrococcus flavus (ATCC 10240) were used. A quantitative determination of penicillin in the samples was accomplished by reading from the standard curves. Sensitivities of the two methods were approximately the same; Micrococcus flavus proved most suitable of the microorganisms employed. At 2, 3, 5 and 20 post-treatment days both test animals were positive; at 10 days three out of four calves examined were positive, whereas at 15 days two out of three calves examined were positive. The residues were most frequently found in the liver, kidney and at the injection sites. Maximum detectable concentrations were at the injections sites, minimum ones in the bone marrow. In the musculature (noninjection site) a small quantity of penicillin was found up to 20 days after the application. Current culinary and technological treatment of positive meat and liver samples did not always suffice for complete inactivation of the penicillin residues. For the tested preparation, a preslaughter withdrawal time of 30 days is recommended.

Abattoirs↗
PubMed1993

Resistance to the antimicrobial agents of bacteria isolated from non-sterile pharmaceuticals.

The in vitro antimicrobial resistance of 391 bacterial strains isolated from 389 samples of oral and topical medicaments was examined. The numbers of strains isolated (and percentage of samples that present them) were: 234 Bacillus (32.1%), 79 Staphylococcus (13.6%), 46 Micrococcus (11.3%), nine Pseudomonas (1.5%), eight Acinetobacter (1.5%), five Enterococcus (1.2%), three Alcaligenes (0.8%), two Escherichia and Enterobacter (0.5%), one each Providencia, Serratia and Streptococcus (0.2%). Gram-positive bacteria were isolated from topical and oral medicaments and Gram-negative rods were detected only in topical medicaments. The 97.4% of Bacillus strains were resistant to lincomycin and B. cereus was resistant to beta-lactam and trimethoprim-sulphamethoxazole. Staphylococcus spp. showed a high percentage of resistant strains to ampicillin (51.8%), tetracycline (40.5%) and trimethoprim-sulphamethoxazole (48.1%). Staphylococcus epidermidis had the highest number of multiresistant strains. The 23.9% of Micrococcus strains were resistant to colistin. Enterococcus and Streptococcus strains showed multiresistance to penicillin G, aminoglycosides and erythromycin. The 61.5% of Gram-negative rod strains showed multiresistance to beta-lactam antibiotics and erythromycin; Pseudomonas spp. were the most resistant.

Bacillus↗
PubMed1996

Aerobic bacteria isolated from blood cultures of patients and their antibiotic susceptibilities in Harare, Zimbabwe.

OBJECTIVE: To assess the extent of involvement of different types of gram positive and gram negative bacteria and incidence of monomicrobial and polymicrobial cases in patients with bacteremia but without a record of the underlying clinical conditions of the patients. Antibiotic susceptibility patterns of isolates were also determined to guide clinicians in the management of such bacteremic cases especially where routine sensitivity testing is not performed. DESIGN: Case series. SETTING: The study comprised patients attending different clinics in Parirenyatwa Hospital, Harare. SUBJECTS: A total of 817 blood cultures from patients, comprising 469 and 348 males and females respectively. There were no records of the underlying clinical conditions of the patients. MAIN OUTCOME MEASURES: Prevalence rates of organisms and their antibiograms using standard techniques and Kirby-Bauer disc diffusion method. RESULTS: Results obtained revealed that only 303(37.1%) of the 817 total samples screened were positive for either monomicrobial or polymicrobial bacteremia. Two hundred and eighteen (71.9%) and 85 of positive cultures were Gram positive and Gram negative bacteria respectively. Coagulase negative staphylococci (CNS) strains were the predominant organisms isolated (42.9%). Other organisms isolated were Staphylococcus aureus (11.6%), Escherichia coli (6.9%), Salmonella spp. (8.3%), Klebsiella spp. (5.3%), whereas Pseudomonas aeruginosa, Haemophilus influenzae, Enterobacter and Micrococcus species each accounted for less than 4%. Antibiogram patterns showed multiple resistance of S. aureus and CNS to Penicillin, Erythromycin and Methicillin. All isolates of S. pyogenes (10), S. pneumoniae (18) and Micrococcus spp (10). were susceptible to penicillin. Ciprofloxacin, Clindamycin, Fusidic acid and Gentamycin were highly active against gram positive organisms except that Gentamycin was inactive against S. pneumoniae. Ceforoxime, Erythromycin and Ceftriazone also showed good activities against Gram positive organisms. All (10) isolates of P. aeruginosa were susceptible to Polymyxin B, Carbenicillin and Ciprofloxacin. Ciprofloxacin, Norfloxacin and Gentamycin were highly active against all Gram negative bacteria. CONCLUSION: For infections due to both Gram positive and Gram negative bacteria, Ciprofloxacin and Gentamycin would be appropriate for therapy whereas Fusidic acid and Clindamycin may, in addition, be recommended for Gram positive organisms. It is also concluded that a prevalence rate of 37.1% of bacteremic cases existed in the sampled population and that monomicrobial cases were more predominant.

Bacteremia↗
PubMed1998

Bacterial infection and endotoxin in female reproductive tract in rats: correlation with the developmental status of preimplantation embryos.

During mammalian preimplantation development, a substantial numbers of embryos are believed to be lost for reasons that are unclear. Using female rats, we investigated whether the developmental status of embryos is influenced by bacterial infection and endotoxin in the reproductive tract. From the vagina of cycling rats (n = 11), 21 bacterial isolates were identified; they were Streptococcus faecalis (S. faecalis; 38%), Escherichia coli (E. coli; 19%), Acinetobactor calcoaceticus (A. calcoaceticus; 14%), and coagulase negative staphylococcus (14%), Micrococcus sp. (5%), Bacillus subtilis (B. subtilis; 5%) and Proteus vulgaris (P. vulgaris; 5%). From the vagina of day 4 pregnant rats (n = 12), 26 isolates were identified; they were S. faecalis (23%), A. calcoaceticus (23%), E. coli (15%), Micrococcus sp. (15%), B. subtilis (8%), P. vulgaris (4%), Staphylococcus aureus (4%), beta-hemolytic streptococcus (4%) and Pseudomonas aeruginosa (4%). Gram negative bacteria found in the vagina of cycling and day 4 pregnant rats were 38% and 46%, respectively. In both, bacterial load was 10(3)-10(5) colony forming units and there was no association with the abnormality of the recovered embryos. However, in two day 4 pregnant animals, pathogenic bacteria (Staphylococcus aureus and beta-hemolytic streptococcus) were isolated and embryos recovered from them were degenerated and deformed. The vagina of day 9 pregnant animals (n = 7) were, however, sterile. Consistently, in all animals, the upper reproductive tract (uterus and oviduct) was devoid of any bacteria and no anaerobic bacteria were isolated from any part of the tract. The levels of endotoxin in the vagina of cycling and day 4 pregnant rats were 1.35 +/- 0.1 and 1.17 +/- 0.1 endotoxin units (EU), respectively. It was undetectable in the oviduct and uterus of all animals (n = 5) except one which showed high levels of endotoxin in uterus (4.5 EU) and oviduct (2.2 EU) and the animal also produced degenerated and deformed embryos. These results indicate that common bacterial flora of vagina may not affect embryo development and the presence of pathogenic bacteria in the vagina and/or endotoxin in reproductive tract could be detrimental to viability of gametes and preimplantation embryos in rats.

Animals↗
PubMed1998

An attempt to use selected strains of bacteria adapted to high concentrations of petroleum oil to increase the effective removal of petroleum products in excess activated sludge in laboratory conditions.

Forty two strains of bacteria were isolated from excess activated sludge from petroleum wastewater treatment plant. The strains were identified and classified to the following groups: Enterobacteriaceae (7 strains), Anitratum (3 strains), Pseudomonas (13 strains), Micrococcus (12 strains), Comamonas (2 strains), Xanthomonas (2 strains), Achromobacter (1 strain) and Vibrio-Aeromonas (1 strain). One of the isolates was found to be a yeast strain. Following preliminary selection ten strains, showing the best growth in medium with oil fraction as sole carbon source, were chosen for further studies. The selected strains belong to Pseudomonas (6 strains), Xanthomonas (2 strains), Micrococcus (1 strain) and Saccharomyces (1 strain). The strains were adapted to high oil concentration (500-2000 mg/L) and an attempt to use them to intensify removal of petroleum products from excess activated sludge was made. The sludge was inoculated with a mixture of the isolated strains. The experiment was carried out three times, each time with a fresh sample of the excess sludge. The obtained results show that the inoculation of activated sludge with the strains active against oil reduced the petroleum products content by 20% in 14 days. The greatest reduction of oil was observed in sludge with the lowest dry weight, that is with the greatest degree of hydration. The dry weight of the excess sludge did not significantly decrease during the course of the experiment, after having been inoculated with the mixture of strains.

Adaptation, Physiological↗
PubMed1963

Statistical study of the spot-plate technique for viable-cell counts.

A statistical study of the spot-plate technique was made for the purpose of establishing an acceptable counting range. The organism used in these studies was Micrococcus lysodeikticus. Standard deviations and coefficients of variation were computed for counts ranging from 20 to 440. The lower and upper limits for acceptable counts, based on coefficients of variation of 10 and 5.8, respectively, were chosen as 100 and 300.

Bacteriological Techniques↗
PubMed1964

CELL-WALL LYSINS OF STAPHYLOCOCCUS AUREUS STRAINS INDUCED BY SPECIFIC TYPING PHAGES.

Ralston, Doris J. (University of California, Berkeley), and Mary McIvor. Cell-wall lysins of Staphylococcus aureus strains induced by specific typing phages. J. Bacteriol. 88:667-675. 1964.-At least 12 different phages induced the formation of soluble lysins (separable from the phages by ultracentrifugation). The lysins caused rapid clearing of heat-killed cells of all strains of Staphylococcus aureus tested, irrespective of the capacity of the phage to form plaques on living cells of the strain. The uninfected cells of the 12 strains contained a second lysin, an autolysin, released upon cellular autolysis. The autolysin preparations differed from the phage-induced lysins, in that they exhibited relatively high activity for lysing Micrococcus lysodeikticus and low activity for strain S. aureus K(1N), and were each specifically inhibited by antiserum prepared against purified autolysin from strain K(1). A third kind of lysin, virolysin, induced by polyvalent phage K, was differentiated from the lysins of the specific phages on the basis of its antigenic specificity and lack of action on M. lysodeikticus. All three kinds of lysins digested the mucopeptide portion of staphylococcal cell walls. No evidence was found that any of these lysins possessed specific host ranges which could be correlated with the lytic host range of the inducing phage.

Animals↗
PubMed1965

HAEMOPROTEINS AND HAEM SYNTHESIS IN FACULTATIVE PHOTOSYNTHETIC AND DENITRIFYING BACTERIA.

1. A simple spectrophotometric method is described for the measurement of various haemoproteins in extracts of photosynthetic and non-photosynthetic bacteria. The method is based on measurements of difference spectra at the Soret maxima. 2. In photosynthetic bacteria of the Athiorhodaceae group the concentration of carbon monoxide-binding haemoprotein and of cytochromes of the b and c types is two to three times as high in anaerobically grown cells as in those grown aerobically. 3. During the adaptation of Rhodopseudomonas spheroides 8253 to form photosynthetic pigments the concentration of each of these haemoproteins increases in parallel with that of the bacteriochlorophyll. 4. The carbon monoxide-binding haemoprotein in aerobically grown Rps. spheroides 8253, in contrast with anaerobically grown cells, is predominantly in the particulate fraction of extracts prepared by ultrasonic vibration. The b- and c-type cytochromes are approximately equally distributed between each fraction in extracts from both types of cell. 5. Extracts of Micrococcus denitrificans grown anaerobically on nitrate contain more cytochromes of the b and c types, as well as of the carbon monoxide-binding pigment, than do those from aerobically grown cells. 6. The activity of ferrochelatase in both Rps. spheroides 8253 and M. denitrificans was similar in extracts from cells grown aerobically and anaerobically, though the haemoprotein content was higher under the latter conditions. Coproporphyrinogen oxidative decarboxylase could not be demonstrated in cell-free extracts of either organism.

Bacteriochlorophylls↗
PubMed1965

HAEM SYNTHASE AND COBALT PORPHYRIN SYNTHASE IN VARIOUS MICRO-ORGANISMS.

1. The preparation of a crude extract of Clostridium tetanomorphum containing cobalt porphyrin synthase but little haem-synthase activity is described. 2. The properties of cobalt porphyrin synthase in the clostridial extracts is compared with the properties of a haem synthase present in crude extracts of the yeast Torulopsis utilis. 3. Cobalt porphyrin synthase in extracts of C. tetanomorphum inserts Co(2+) ions into the following dicarboxylic porphyrins in descending order of rate of insertion: meso-, deutero- and proto-porphyrins. Esterification renders meso- and deutero-porphyrins inactive as substrates. Neither the tetracarboxylic (coproporphyrin III) nor the octacarboxylic (uroporphyrin III) compounds are converted into cobalt porphyrins by the extract, but the non-enzymic incorporation of Co(2+) ions into these two porphyrins is rapid. These extracts are unable to insert Mn(2+), Zn(2+), Mg(2+) or Cu(2+) ions into mesoporphyrin. 4. Crude extracts of T. utilis readily insert both Co(2+) and Fe(2+) ions into deutero-, meso, and proto-porphyrins. Unlike the extracts of C. tetanomorphum, these preparations catalyse the insertion of Co(2+) ions into deuteroporphyrin more rapidly than into mesoporphyrin. This parallels the formation of haems by the T. utilis extract. 5. Cobalt porphyrin synthase is present in the particulate fraction of the extracts of C. tetanomorphum but requires a heat-stable factor present in the soluble fraction. This soluble factor can be replaced by GSH. 6. Cobalt porphyrin synthase in the clostridial extract is inhibited by iodoacetamide and to a smaller extent by p-chloromercuribenzoate and N-ethylmaleimide. The haem synthases of T. utilis and Micrococcus denitrificans are also inhibited by various thiol reagents.

Biochemical Phenomena↗
PubMed1965

THE ACTION OF HOT FORMAMIDE ON BACTERIAL CELL WALLS.

1. The cell walls of Corynebacterium tritici contain much carbohydrate and their mucopeptide contains diaminobutyric acid instead of lysine or diaminopimelic acid. They are resistant to lysozyme. 2. The residue after extraction with hot formamide contains only about 10% less carbohydrate but is attacked by lysozyme. Lysozyme also slowly attacks cell walls treated with fluorodinitrobenzene and more rapidly cell walls that have been N-acetylated. 3. All these processes block the free gamma-amino groups of diaminobutyric acid present in the untreated cell wall. Hot formamide introduces formyl groups, as shown by its ability to make formylglycine and diformyl-lysine under the same conditions. 4. N-Formyl groups are also introduced into the cell walls of Micrococcus lysodeikticus by hot formamide, but this change increases only slightly their already great sensitivity to lysozyme. N-Acetylation also increases sensitivity to lysozyme.

Bacillus megaterium↗
PubMed1963

UNMINERALIZED FOSSIL BACTERIA.

Unmineralized bacterial cells, mostly Micrococcus sp., but including also Streptococcus sp. and Actinomyces sp., were found in enormous numbers in lake beds of the Newark Canyon Formation of Early Cretaceous age, Eureka County, Nevada. The micrococci are black, and have an average diameter about 0.5 micro. Similar black micrococci (0.4 to 0.7 micro) were found in profusion in the bottom mud of Green Lake, New York. About 80 percent of this mud consists of minute idiomorphic calcite crystals and about 20 percent of these contain enormous numbers of the black micrococci. It is suggested that the Early Cretaceous bacterial cells owe their preservation to occlusion in calcite crystals that grew in a black, bacterial mud in a meromictic lake in which part of the Newark Canyon Formation accumulated.

Actinomyces↗
PubMed1963

Mechanism of protection of cells by spermine against lysozyme-induced lysis.

Grossowicz, Nathan (Hebrew University Hadassah Medical School, Jerusalem, Israel) and Miriam Ariel. Mechanism of protection of cells by spermine against lysozyme-induced lysis. J. Bacteriol. 85:293-300. 1963.-Spermine (1 to 5 x 10(-3)m) was found to prevent lysis of Micrococcus lysodeikticus cells by lysozyme. This protection is due to the rapid and efficient stabilization by spermine of the protoplasts formed by lysozyme, and not to interference with the enzymatic activity. This conclusion concerning the spermine effect is based on chemical and microscopic evidence: (i) the amount of hexosamine, released from lysozyme-treated cells, was equal to or even higher in the presence of spermine than in its absence; (ii) microscopic and electron microscopic pictures showed clearly that the spermine-protected structures resembled protoplasts. On the other hand, the "spermine protoplasts" showed a high stability against hypotonic conditions in comparison with "sucrose protoplasts." The spermine-protoplast complex was very stable and could not be destroyed by water and various agents (NaCl, KCl, MgCl(2), cadaverine, and putrescine). A number of bases such as histamine, d-histidine, and streptomycin exhibited an effect similar to that of spermine, while diamines like cadaverine, putrescine, basic amino acids (lysine, arginine, l-histidine), as well as cations like magnesium, were virtually inactive.

Bacteriolysis↗
PubMed1963

ROLE OF FERREDOXIN IN THE METABOLISM OF MOLECULAR HYDROGEN.

Valentine, R. C. (University of Illinois, Urbana) and R. S. Wolfe. Role of ferredoxin in the metabolism of molecular hydrogen. J. Bacteriol. 85:1114-1120. 1963.-The metabolism of molecular hydrogen by Clostridium pasteurianum, Micrococcus lactilyticus (Veillonella alcalescens), and several other anaerobic bacteria was studied. Oxidation of hydrogen, using several electron-accepting substrates including triphosphopyridine nucleotide, uric acid, xanthine, nitrite, and hydroxylamine, required ferredoxin in conjunction with hydrogenase. Evolution of hydrogen from pyruvate, alpha-ketoglutarate, hypoxanthine, and dithionite was mediated by ferredoxin. On the basis of these findings, a unitary hypothesis for biological hydrogen evolution is proposed in which ferredoxin plays a key role.

Chromatography↗
PubMed1963

RADIATION-RESISTANT, PIGMENTED COCCUS ISOLATED FROM HADDOCK TISSUE.

Davis, Norman S. (Massachusetts Institute of Technology, Cambridge), Gerald J. Silverman, and Edmund B. Masurovsky. Radiation-resistant, pigmented coccus isolated from haddock tissue. J. Bacteriol. 86:294-298. 1963.-An orange-brown, catalase-positive coccus was isolated from irradiated haddock. The new coccus was found to consist of rough and smooth strains as well as strains possessing appreciably less pigment. The smooth strain (248) was more radioresistant to gamma radiation than the rough strain, and at higher radiation doses was of comparable resistance to Micrococcus radiodurans. The less-pigmented strain was as radio-resistant as its parent strain (248). Although morphologically similar to other, but less-resistant, micrococci, the coccus differed by growing slowly on solid media, and was unable to grow in 7% salt. It was distinguished from M. radiodurans by being smaller in size and in being capable of reducing nitrate to nitrite and hydrolyzing gelatin.

Animals↗
PubMed1964

FORMATE--PYRUVATE EXCHANGE REACTION IN STREPTOCOCCUS FAECALIS. II. REACTION CONDITIONS FOR CELL EXTRACTS.

Oster, M. O. (A. & M. College of Texas, College Station), and N. P. Wood. Formate-pyruvate exchange reaction in Streptococcus faecalis. II. Reaction conditions for cell extracts. J. Bacteriol. 87:104-113. 1964.-In contrast to intact cells of Streptococcus faecalis, no stimulation of the formate-pyruvate exchange reaction was observed in cell extracts when yeast extract was added to the reaction mixture. A heated extract of Micrococcus lactilyticus, vitamin K(5), ferrous sulfate, and ferrous ammonium sulfate stimulated an active exchange by protecting the system from oxygen. Tetrahydrofolate, 2,3-dimercaptopropanol, and sodium sulfide provided partial protection, whereas ascorbate, glutathione, sodium hydrosulfite, ammonium sulfide, and sodium bisulfite gave insufficient protection or were inhibitory. Oxidation-reduction (O-R) indicators were not inhibitory and were used to estimate the O-R potentials of reaction mixtures. A potential at least as negative as -125 mv was estimated to be necessary to preserve or initiate formate-pyruvate exchange activity. The reaction operated over a narrow pH range when strict anaerobic conditions were not maintained but, when the system was suitably poised, the pH range was broader. The influence of high phosphate concentrations was less under strictly anaerobic conditions, and orthophosphate could be replaced by small amounts of pyrophosphate. Effect of temperature, time, and amount of extract is presented. Addition of reduced benzyl viologen and hydrogen-saturated palladium in the buffer during 8 hr of dialysis prevented inactivation of extracts. Recovery of activity could be obtained after ammonium sulfate treatment when a combination of palladium chloride, neutral red, and hydrogen bubbling were used.

Adenosine Triphosphate↗
PubMed1964

SPECTROCHEMICAL ANALYSIS OF INORGANIC ELEMENTS IN BACTERIA.

Rouf, M. A. (Washington State University, Pullman). Spectrochemical analysis of inorganic elements in bacteria. J. Bacteriol. 88:1545-1549. 1964.-Quantitative spectrochemical analyses of inorganic elements in the vegetative cells of Escherichia coli, Sphaerotilus natans, Micrococcus roseus, Bacillus cereus, and the spores of B. cereus were made. The following elements were found to be present in the ash samples: B, Na, Mg, Al, Si, P, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, Sr, S, Ag, Sn, Ba, Pb, V, and Mo. These could be divided into major, minor, and trace elements, depending on the relative amounts in the cells. Mg, P, K, and S were considered as the major elements; Ca, Fe, Zn, and, perhaps, Cu and Mn as the minor elements, and the rest as trace elements. Mg concentrations were higher in the cells of the gram-positive M. roseus and B. cereus than in the gram-negative E. coli and S. natans. The latter organism contained 2.6% Fe(2)O(3) (dry weight basis). The vegetative cells of B. cereus were higher in Mg, P, K, Na, Ag, and lower in Si, Ca, Zn, Mn, and Cu than were its spores.

Bacillus cereus↗