Influence of cations on growth of thermophilic Geobacillus spp. and Anoxybacillus flavithermus in planktonic culture

Free ions of Na(+), K(+), Ca(2+), and Mg(2+) influenced the optical density of planktonic cultures of thermophilic bacilli. Anoxybacillus flavithermus E16 and Geobacillus sp. strain F75 (milk powder manufacturing plant isolates) and A. flavithermus DSM 2641 and G. thermoleovorans DSM 5366 were studied. Ca(2+) and Mg(2+) were associated with increases in optical density more so than Na(+) and K(+). Overall, it appeared that Ca(2+) and/or Mg(2+) was required for the production of protein in thermophilic bacilli, as shown by results obtained with A. flavithermus E16, which was selected for further study.     

Encapsulated in silica: genome, proteome and physiology of the thermophilic bacterium Anoxybacillus flavithermus WK1

Background

Gram-positive bacteria of the genus Anoxybacillus have been found in diverse thermophilic habitats, such as geothermal hot springs and manure, and in processed foods such as gelatin and milk powder. Anoxybacillus flavithermus is a facultatively anaerobic bacterium found in super-saturated silica solutions and in opaline silica sinter. The ability of A. flavithermus to grow in super-saturated silica solutions makes it an ideal subject to study the processes of sinter formation, which might be similar to the biomineralization processes that occurred at the dawn of life.

Results

We report here the complete genome sequence of A. flavithermus strain WK1, isolated from the waste water drain at the Wairakei geothermal power station in New Zealand. It consists of a single chromosome of 2,846,746 base pairs and is predicted to encode 2,863 proteins. In silico genome analysis identified several enzymes that could be involved in silica adaptation and biofilm formation, and their predicted functions were experimentally validated in vitro. Proteomic analysis confirmed the regulation of biofilm-related proteins and crucial enzymes for the synthesis of long-chain polyamines as constituents of silica nanospheres.

Conclusions

Microbial fossils preserved in silica and silica sinters are excellent objects for studying ancient life, a new paleobiological frontier. An integrated analysis of the A. flavithermus genome and proteome provides the first glimpse of metabolic adaptation during silicification and sinter formation. Comparative genome analysis suggests an extensive gene loss in the Anoxybacillus/Geobacillus branch after its divergence from other bacilli.     

Ranges of Regulation of Sodium, Potassium, Calcium, Magnesium Concentrations in Plasma, Erythrocytes, and Muscle Tissue of Rutilus rutilus under Natural Conditions

As a result of studies for 3 years on the roach Ratilus ratilus under natural conditions, it was shown that the Na, K, Ca, and Mg content in the blood plasma, erythrocytes, and muscle tissue as well as muscle water were maintained year after year within definite ranges characterizing normal values for these parameters. Comparison of variations in the Na, K, Ca, Mg blood plasma concentrations in different fish species revealed the presence of common limits for each of these elements. Throughout the year the most essential changes in the roach blood and tissue cation levels were found during reproduction period. During spawning the fish are characterized by the state of acute stress with parameters indicating a decrease in stability and exhaustion of adaptive possibilities in animals. Intensification of defense reactions, including those providing maintenance of the water–salt homeostasis occurs shortly before spawning for a preliminary preparation to the stress situation.     

Changes in Total Body Calcium and Sodium in Osteomalacia

Serial measurements were made of total body calcium and sodium, using whole body neutron activation analysis, in six patients being treated for osteomalacia. All showed a rise in total body calcium ranging from 3 to 30%; this continued for up to 24 months after the start of treatment, though complete healing had apparently occurred after 6 months on the basis of histological examination of biopsy specimens of bone. As the total body calcium rose there was a fall in the non-exchangeable sodium pool in bone.     

Concentrations of Sodium, Potassium, Magnesium, and Iron in the Serum of Dairy Cows with Subclinical Ketosis

Serum concentrations of sodium, potassium, magnesium, and iron were measured in dairy cows with subclinical ketosis. Compared with healthy cows, the subclinically ketotic cows had significantly higher levels of non-esterified fatty acids and β-hydroxybutirate in serum and significantly lower levels of blood glucose (p?相似文献   

Anoxybacillus and Geobacillus biofilms in the dairy industry: effects of surface material,incubation temperature and milk type

Abstract

Anoxybacillus (A. flavithermus, A. kamchatkensis subsp. asachharedens, A. caldiproteolyticus and A. tepidamans) and Geobacillus (two strains of G. thermodenitrificans, G. thermoglucosidans and G. vulcanii) isolates and reference strains in whole milk were evaluated for their biofilm production on six different abiotic surfaces. G. thermodenitrificans DSM 465^T had the highest cell counts (>4 log₁₀ CFU cm^?2) on glass and stainless steel (SS) at 55 and 65?°C, respectively. G. thermodenitrificans D195 had the highest counts on SS at 55?°C (>5 log₁₀ CFU cm^?2) and polyvinyl chloride (PVC) at 65?°C (>4 log₁₀ CFU cm^?2), indicating the existence of strain variation. The ideal surfaces for all strains were SS and glass at 55?°C, but their preferences were polystyrene and SS at 65?°C. Moreover, Anoxybacillus members were more prone to form biofilms in skim milk than in semi-skim and whole milk, whereas the results were the opposite for Geobacillus. Both the attachment and sporulation of Geobacillus in whole milk was higher than in semi-skim or skim milk. This study proposes that the surface material, temperature and milk type had a cumulative effect on biofilm formation.     

Potassium, Calcium, Magnesium, and Sodium Levels in Biological Samples of Hypertensive and Nonhypertensive Diabetes Mellitus Patients

There is accumulating evidence that the metabolism of several essential elements is altered in diabetes mellitus and that these nutrients might have specific roles in the pathogenesis and progress of this disease. The aim of the present study was to compare the level of essential elements, potassium (K), calcium (Ca), magnesium (Mg), and sodium (Na), in biological samples (whole blood, urine, and scalp hair) of patients who have hypertensive diabetes mellitus type 2 (n = 254) and nonhypertensive diabetes mellitus type 2 (n = 228) with those of nondiabetic as control subjects (n = 182; age range of both genders 45-75). The element concentrations were measured by means of an atomic absorption spectrophotometer after microwave-induced acid digestion. The validity and accuracy was checked by conventional wet acid digestion method and using certified reference materials. The overall recoveries of all elements were found in the range of 99.1-99.9% of certified values. The results of this study showed that the mean values of K, Mg, and Ca were significantly reduced, while Na level were higher in blood and scalp hair samples of hypertensive diabetic (HD) patients and nonhypertensive diabetic (NHD) patients as compared to control subjects of both genders (p < 0.05), but level of K in the biological samples of nonhypertensive diabetic patient was found to be higher, but it was not significant (p = 0.05).The urinary levels of these elements were found to be higher in both HD and NHD patients than in the age-matched healthy controls. These results are consistent with those obtained in other studies, confirming that deficiency and efficiency of some essential trace metals may play a role in the development of diabetes mellitus.     

Rapid differentiation and enumeration of the total, viable vegetative cell and spore content of thermophilic bacilli in milk powders with reference to Anoxybacillus flavithermus

AIMS: The development of a rapid method for the selective detection and enumeration of the total and viable vegetative cell and spore content of thermophilic bacilli in milk powder by PCR. METHODS AND RESULTS: Quantitative PCR and microscopy indicate the presence of up to 2.9 log units more cells in milk powder than accounted for by plate counting due to the majority of cells being killed during milk processing. Two approaches for viable and dead cell differentiation of thermophilic bacilli by quantitative PCR were evaluated, these being the nucleic binding dye ethidium monoazide (EMA) and DNase I digestion. The former agent exposed to a viable culture of Anoxybacillus flavithermus caused considerable cell inactivation. In contrast, DNase I treatment had no effect on cell viability and was utilized to develop DNA extraction methods for the differential enumeration of total, viable vegetative cells and spores in milk powder. Moreover, the methods were further applied and evaluated to 41 factory powder samples taken throughout eight process runs to assess changes in numbers of vegetative cells and spores with time. DNase I treatment reduced vegetative cell numbers enumerated with PCR by up to 2.6 log units. The quantification of spores in the factory milk powders investigated indicates on average the presence of 1.2 log units more spores than determined by plate counting. CONCLUSIONS: The method presented in this study provides the ability to selectively enumerate the total and viable cell and spore content of reconstituted milk. SIGNIFICANCE AND IMPACT OF THE STUDY: The current study provides a tool to monitor the extent of thermophilic contamination during milk powder manufacturing 60-90 min after sampling.     

Effects of Different Calcium, Magnesium, and Zinc Concentrations Supplemented on Hepatopancreatic Cell Proliferation of Kuruma Prawn, Penaeus japonicus

The effects of different calcium (Ca(2+)), magnesium (Mg(2+)), and zinc (Zn(2+)) concentrations supplemented on hepatopancreatic cell proliferation of kuruma prawn, Penaeus japonicus was studied. The culture system consists of medium 199 (M 199) supplemented with 0.060 mol/L NaCl, 1.011 g/L glucose, 1,000 UI/ml penicillin, 1,000 μg/ml treptomycin, heat inactivated fetal calf serum (FCS) 20% for primary cell culture and 10% for subculture. The RNA/DNA ratio of the cell cultures was measured. The results show that the cell division of hepatopancreatic cells of P. japonicus was enhanced by the optimal concentration of inorganic salt (Ca(2+), 1.0 g/L; Mg(2+), 5.0 g/L; Zn(2+), 80 μg/L). The hepatopancreatic cell culture system and improved culture conditions described here will be very useful for in vitro experiments to study viruses responsible for infections in shrimp leading to tremendous economic losses.     

Effect of Magnesium Deficiency on Various Mineral Concentrations in Rat Liver

Magnesium (Mg) deficiency is well known to affect metabolism of some trace minerals. We investigated the effect of Mg deficiency on hepatic concentration of various minerals in rats. Twelve 5-week-old male rats were divided into the groups given a control diet and an Mg-deficient diet. After 4?weeks, liver sample was collected from each rat. The concentrations of 36 minerals were simultaneously determined by a semiquantitative method of inductively coupled plasma-mass spectrometry (ICP-MS). The semiquantitative analysis showed that Mg deficiency significantly increased iron (Fe), copper (Cu), zinc (Zn), gallium (Ga), yttrium (Y), zirconium (Zr), molybdenum (Mo), rhodium (Rh), silver (Ag), and barium (Ba) concentrations, and significantly decreased scandium (Sc) and niobium (Nb) concentrations in rat liver. Then, hepatic Fe, Cu, Zn, Sc, Zr, and Mo concentrations were quantitatively measured, which indicated the similar effects as observed by the semiquantitative analysis. Additionally, the semiquantitative measurements of these minerals were highly correlated to these measurements with the quantitative method, but the measurements were not completely consistent between these analyses. The present study is the first research indicating the changes of hepatic Ga, Y, Zr, Mo, Rh, Ag, Ba, Sc, and Nb concentrations in Mg-deficient rats. The present study also indicates that the semiquantitative analysis with ICP-MS is a valid method for screening analysis to investigate various mineral concentrations in animal tissues.     

胞外镁离子对SD成年大鼠心肌细胞胞内钙信号的影响

目的：研究胞外不同浓度的镁离子对SD成年大鼠心肌细胞钙瞬变的影响。方法：采用激光共聚焦显微镜系统同步配合阈上电刺激探测心肌细胞钙瞬变。结果：胞外低浓度的镁离子（0 mmol /L,0.5 mmol /L; 正常镁离子浓度为1 mmol/L）可以升高钙瞬变的峰值（P〈0.05）,但不影响钙瞬变的持续时间（以钙瞬变的半高宽表示）（P〉0.05）;胞外高浓度的镁离子（2.5 mmol /L,5 mmol /L,10 mmol /L）均可抑制钙瞬变的峰值（P〈0.05）;其中5 mmol/L和10 mmol/L的胞外镁还能延长钙瞬变的持续时间（P〈0.05）。结论：正常情况下镁对心肌细胞钙瞬变有抑制作用。     

Changes in the Distribution of Magnesium, Potassium, Calcium and Phosphorus during Growth of Cucurbita Seedlings

Ockenden, I. and Lott, J. N. A. 1988. Changes in the distributionof magnesium, potassium, calcium and phosphorus during growthof Cucurbita seedlings—J. exp. Bot. 39: 973–980. Etiolated seedlings of Cucurbita maxima cv. Warted Hubbard andCucurbita andreana, grown in distilled water, showed considerablegrowth. However, only a small percentage of the minerals storedin the large cotyledons was mobilized to the root-shoot axisof the etiolated seedlings. The proportion of minerals removedfrom the cotyledons to the root-shoot axis was about two-timeshigher in C. andreana than in C. maxima. When the seedlingswere grown in distilled water in the presence of light, thepercentage of cotyledon mineral content that was mobilized waslower than the amount mobilized during growth in the dark. Cotyledonsof light-grown seedlings that were given adequate nutrients,took up minerals from the medium. These fully-expanded and photosyntheticcotyledons had slightly more P and Mg than did the cotyledonsof the dry embryos but had increased their K content 5-foldand their Ca content 50-fold. Key words: Cucurbita, minerals, seeds, seedings, NAA     

Relationship Between Serum Calcium and Magnesium Concentrations and Metabolic Syndrome Diagnostic Components in Middle-Aged Korean Men

It is thought that calcium and magnesium may be related to metabolic disorders such as obesity and metabolic syndrome; however, to date, there have been few studies investigating the association between serum calcium and magnesium levels and metabolic syndrome in middle-aged male adults. We aimed to investigate the association between serum calcium and magnesium levels and metabolic syndrome in Korean middle-aged male adults. Study subjects included 213 men aged 30∼60 years. MetS risk score is determined by adding the number of risk factors, waist circumference, triacylglyceride (TG), HDL cholesterol, glucose, and blood pressure (BP). The study population was divided into three groups according to the MetS risk score: group I (MetS risk score ≤1; n = 106), group II (MetS risk score = 2; n = 51), and group III (MetS risk score ≥3; n = 56). The serum Ca, according to increase of MetS risk score, was significantly higher (p < 0.001), and there was no significant difference in serum Mg concentration among the three groups. Subjects with high TG and high BP had higher serum calcium levels than those without such abnormalities. Subjects with higher glucose had lower serum magnesium levels than those without such abnormality. The correlation analysis indicated that the serum Ca had positive correlations with the MetS risk score (r = 0.1769, p < 0.01), serum TG (r = 0.2516, p < 0.001), and DBP (r = 0.2246, p < 0.01). The correlation analysis indicated that the serum Mg had an inverse relationship with serum glucose (r = −0.2404, p < 0.001). In conclusion, serum Ca had positive association with TG and BP, while serum Mg had negative association with serum glucose after adjusting age and BMI among the middle-aged Korean male adults.     

Monitoring Changes in Membrane Polarity,Membrane Integrity,and Intracellular Ion Concentrations in Streptococcus pneumoniae Using Fluorescent Dyes

Membrane depolarization and ion fluxes are events that have been studied extensively in biological systems due to their ability to profoundly impact cellular functions, including energetics and signal transductions. While both fluorescent and electrophysiological methods, including electrode usage and patch-clamping, have been well developed for measuring these events in eukaryotic cells, methodology for measuring similar events in microorganisms have proven more challenging to develop given their small size in combination with the more complex outer surface of bacteria shielding the membrane. During our studies of death-initiation in Streptococcus pneumoniae (pneumococcus), we wanted to elucidate the role of membrane events, including changes in polarity, integrity, and intracellular ion concentrations. Searching the literature, we found that very few studies exist. Other investigators had monitored radioisotope uptake or equilibrium to measure ion fluxes and membrane potential and a limited number of studies, mostly in Gram-negative organisms, had seen some success using carbocyanine or oxonol fluorescent dyes to measure membrane potential, or loading bacteria with cell-permeant acetoxymethyl (AM) ester versions of ion-sensitive fluorescent indicator dyes. We therefore established and optimized protocols for measuring membrane potential, rupture, and ion-transport in the Gram-positive organism S. pneumoniae. We developed protocols using the bis-oxonol dye DiBAC₄(3) and the cell-impermeant dye propidium iodide to measure membrane depolarization and rupture, respectively, as well as methods to optimally load the pneumococci with the AM esters of the ratiometric dyes Fura-2, PBFI, and BCECF to detect changes in intracellular concentrations of Ca²⁺, K⁺, and H⁺, respectively, using a fluorescence-detection plate reader. These protocols are the first of their kind for the pneumococcus and the majority of these dyes have not been used in any other bacterial species. Though our protocols have been optimized for S. pneumoniae, we believe these approaches should form an excellent starting-point for similar studies in other bacterial species.     

Effect of Dwarfing Interstocks on Xylem Sap Composition in Apple Trees: Effect on Nitrogen, Potassium, Phosphorus, Calcium and Magnesium Content

This paper concerns nutrient concentrations in xylem sap collectedfrom above and below M.8, M.9, M.26 and M.7 dwarfing interstocks.The sap flowing from above an interstock had lower concentrationsof nutrients than that from the rootstock levels and these differencesincreased with the dwarfing effect of the interstock. There were indications that nutrient concentrations were enhancedbelow interstocks but were reduced in the sap flowing from theinterstocks into the scions. Generally these reductions weregreater the more dwarfing the effect of the interstock. Analyses of sap from above, mid-way along and below interstocksindicated that the changes in content were produced in, or closeto, the graft union between scion and interstock.     

The Role of Calcium,Magnesium, and Zinc in Pre-Eclampsia

Pre-eclampsia is the most common medical complication of pregnancy associated with increased maternal and infant mortality and morbidity. Its exact etiology is not known, although several evidences indicate that various elements might play an important role in pre-eclampsia. This study was carried out to analyze and to compare the concentration of calcium, magnesium, and zinc in the serum of women with pre-eclampsia and in normal pregnant women. Fifty clinically diagnosed patients with pre-eclampsia (25 with mild and 25 with severe pre-eclampsia) and 50 normal pregnant controls were enrolled in this study. The serum calcium, magnesium, and zinc levels were estimated with an atomic absorption spectrophotometer. The mean serum levels of calcium, magnesium, and zinc in normal pregnant group were 2.45 ± 0.18 mmol/L, 0.79 ± 0.13 mmol/L, and 15.64 ± 2.4 μmol/L, respectively, while in mild pre-eclamptic group, these were 2.12 ± 0.15 mmol/L, 0.67 ± 0.14 mmol/L, and 12.72 ± 1.7 μmol/L, respectively. Serum levels in severe pre-eclamptic group were 1.94 ± 0.09 mmol/L, 0.62 ± 0.11 mmol/L, and 12.04 ± 1.4 μmol/L, respectively. These results indicate that reduction in serum levels of calcium, magnesium, and zinc during pregnancy might be possible contributors in etiology of pre-eclampsia, and supplementation of these elements to diet may be of value to prevent pre-eclampsia.