Anaerobic fructolysis, lactic acid and heat production of bull spermatozoa

1964 ◽  
Vol 159 (975) ◽  
pp. 291-296 ◽  
Keyword(s):  
Lactic Acid ◽  
Standard Deviation ◽  
Heat Production ◽  
Metabolic Pathways ◽  
Enthalpy Change

A comparison has been made of the fructose broken down, lactic acid produced and heat evolved by washed anaerobic bull spermatozoa. On the average, 19·5% more fructose was broken down than lactic acid produced (standard deviation 2·0%, 95% fiducial limits 15·2 and 23·8%). The amount of heat produced by the spermatozoa was on the average only 9·7% more than the heat expected on the basis of the enthalpy change associated with the breakdown of that part, 80·5%, of the fructose which was broken down to lactic acid. The standard deviation of the 9·7% was 3·4 %, with 95% fiducial limits 2·3 and 17·1%. The implications of these findings are discussed in relation to the metabolic pathways in anaerobic bull spermatozoa.

Anaerobic heat production of bull spermatozoa

1957 ◽  
Vol 147 (928) ◽  
pp. 316-331 ◽  
Keyword(s):  
Lactic Acid ◽  
Seminal Plasma ◽  
Heat Production ◽  
Enthalpy Change ◽  
Partial Neutralization ◽  
Micro Calorimeter

A micro-calorimeter, suitable for detecting rates of heat production of the order of 1 mcal/h in about 2·3 ml. fluid, is described. Measurements have been made with it of the anaerobic heat production of bull spermatozoa in semen. The result, for the first hour, 220 ±15 mcal/10 9 live spermatozoa/h at 37°C, is consistent with the hypothesis that, in the first hour of incubation, the heat produced is derived from the enthalpy change associated with the breakdown of fructose to lactic acid. In the second hour of incubation the heat produced by the spermatozoa, 111 ± 18 mcal/10 9 live spermatozoa/h at 37°C, was sometimes greater than that associated with fructolysis. Measurements were also made of the heat production of spermatozoa killed or inactivated by various methods, of seminal plasma, and of the heat of partial neutralization of seminal plasma by lactic acid.

P0031AURINE METABOLOMICS: AN EMERGING TOOL FOR DISSECTING BIOLOGICAL ABERRATIONS UNDERLYING RENAL DYSFUNCTION IN BARDET-BIEDL SYNDROME

2020 ◽  
Vol 35 (Supplement_3) ◽  
Author(s):  
Miriam Zacchia ◽  
Emanuela Marchese ◽  
Marianna Caterino ◽  
Margherita Ruoppolo ◽  
Giovambattista Capasso
Keyword(s):  
Lactic Acid ◽  
Kidney Disease ◽  
Renal Disease ◽  
Renal Dysfunction ◽  
Metabolic Pathways ◽  
Healthy Subjects ◽  
Hexadecenoic Acid ◽  
Kidney Dysfunction ◽  
Bardet Biedl Syndrome ◽  
Wide Range

Abstract Background and Aims Bardet Biedl Syndrome (BBS) is a rare genetic disorder characterized by a wide range of organ dysfunction, including kidney disease. The severity of renal dysfunction is highly variable in this setting, ranging from tubular defects to the end stage renal disease, with poor genotype-phenotype correlation. Proteomics and metabolomics are powerful tools able to contribute to the better understanding of molecular basis of disease conditions. Our previous studies demonstrated that the urinary proteomic pattern of BBS patients differed from that of healthy subjects, with a set of deregulated proteins including cell adhesion and extracellular matrix organization proteins (1). The present study aims to characterize urine metabolomic profile of BBS patients, in order to identify both 1) potential disease biomarkers and 2) aberrant metabolic pathways underlying renal disease Method To this end, in the pilot study urine samples have been collected from 14 adult BBS patients and have been compared with healthy volunteers, using an untargeted strategy. In the confirmation study, 24 BBS patients with wide range of kidney dysfunction have been enrolled, and additional control groups, besides healthy subjects, were included: 1) age-gender-matched chronic kidney disease patients by other causes and 2) obese individuals. Results Several metabolites were de-regulated in BBS patients compared with normal subjects (lactic acid, glycolic acid,3-Hydroxypropionic acid, pyruvic acid, 3-hydroxyisobutyric acid, 2-ethyl-3-hydroxy-propionic acid, succinic acid, fumaric acid, erythropentonic acid, 2-hydroxyglutaric acid, 4-hydroxyphenyllactic acid, 3,4-pyridinedicarboxylic acid, retinoic acid, 4-hydroxyphenylacetic acid, palmitic acid, 9-Hexadecenoic acid, oleic acid and 9-Octadecenoic acid). The clusterization performed by MetaboAnalyst tool, revealed a possible deregulation of different metabolic pathways, including glycolysis, TCA cycle, pyruvate metabolism, lipids biosynthesis and glutamate metabolism (p-value <0.01) (figure 1); some of these pathways were described as de-regulated in other ciliopathies (2). In the confirmation study (on-going studies) some metabolites, including lactic acid and intermediates of Krebs cycle, correlated with kidney dysfunction only in the BBS group. Conclusion These findings suggest that urine metabolomic fingerprint of BBS patients is different from that of healthy subjects and indicate a possible deregulation of several metabolic pathways; some urinary molecules correlated with kidney dysfunction only in BBS patients, suggesting the specificity of these results.

scholarly journals Metabolism of propane-1:2-diol infused into the rumen of sheep

1972 ◽  
Vol 27 (3) ◽  
pp. 553-560 ◽  
Author(s):  
J. L. Clapperton ◽  
J. W. Czerkawski
Keyword(s):  
Carbon Dioxide ◽  
Fatty Acids ◽  
Acetic Acid ◽  
Lactic Acid ◽  
Polyethylene Glycol ◽  
Energy Metabolism ◽  
Heat Production ◽  
Volatile Fatty Acids ◽  
Carbon Dioxide Production ◽  
Total Volatile

1. Propane-1:2-diol (loog/d) was infused through a cannula into the rumen of sheep receiving a ration of hay and dried grass. The concentration of volatile fatty acids, propanediol, lactic acid and of added polyethylene glycol, and the pH of the rumen contents were measured. The energy metabolism of the sheep was also determined.2. Most of the propanediol disappeared from the rumen within 4 h of its infusion. The infusion of propanediol resulted in a 10% decrease in the concentration of total volatile acids; the concentration of acetic acid decreased by about 30%, that of propionic acid increased by up to 60% and there was no change in the concentration of butyric acid.3. The methane production of the sheep decreased by about 9% after the infusion of propanediol and there were increases in the oxgyen consumption, carbon dioxide production and heat production of the animals; each of these increases was equivalent to about 40% of the theoretical value for the complete metabolism of 100 g propanediol.4. It is concluded that, when propanediol is introduced into the rumen, a proportion is metabolized in the rumen and a large proportion is absorbed directly. Our thanks are due to Dr J. H. Moore for helpful discussions, to Mr D. R. Paterson, Mr J. R. McDill and Mr C. E. Park for looking after the animals and to Miss K. M. Graham, Miss A. T. McKay and Mrs C. E. Ramage for performing the analyses.

scholarly journals The heat production in isometric and isotonic twitches

1930 ◽  
Vol 107 (749) ◽  
pp. 115-131 ◽  
Keyword(s):  
Lactic Acid ◽  
Heat Production ◽  
Isometric Contraction ◽  
Room Temperature ◽  
Probable Error ◽  
Isotonic Contraction ◽  
Complete Relaxation ◽  
Initial Load ◽  
The Difference ◽  
Isotonic Contractions

In a recent paper from Meyerhof's laboratory P. Rothschild (1930) has shown that in a series of isometric twitches of a frog's gastrocnemius or semi-membranosus considerably more lactic acid may be liberated than in the same number of isotonic twitches with the same initial load: while with sartorius there may be little or no difference. 90 to 150 shocks were applied, at intervals of 5 to 10 seconds, at room temperature (11° C. to 17° C.), and either directly or to the nerve: the intervals were sufficient to allow complete relaxation between twitches and the number of twitches was not so great as to cause appreciable fatigue. With semi-membranosus, with an initial load of 10 or 20 g. the lactic acid in the isotonic averaged about 35 per cent. less than in the isometric twitches: with gastrocnemius stimulated through its nerve following six results were obtained at 15° to 17° C. in 92 to 102 twitches: Initial load: g. ............ 25 20 20 20 10 10 After-load (isotonic): g. ............. 13 50 50 50 140 140 Deficit due to shortening: p. c. ............. 70 49 64 76 34 25 Thus in an isotonic contraction with considerable shortening the lactic acid may be ½ to ⅓ of the amount in an isometric contraction with the same initial load: while when the shortening is smaller (greater after-load) the difference may be less (last two experiments). With sartorius, however, in 110 to 150 contractions at 12° C. to 17° C., there was a slight excess of lactic acid in the isotonic contractions, averaging about 8 per cent. The smallness of the difference was regarded by Rothschild as insignificant, in view of the probable error of his estimations: in this, as will be seen, he unduly depreciated the accuracy of his own observations: his difference was probably genuine.

Biosynthesis and role of 3-methylbutanal in cheese by lactic acid bacteria: Major metabolic pathways, enzymes involved, and strategies for control

2015 ◽  
Vol 57 (2) ◽  
pp. 399-406 ◽  
Author(s):  
Muhammad Inam Afzal ◽  
Citlalli Celeste González Ariceaga ◽  
Kenza-Amel Boulahya ◽  
Muriel Jacquot ◽  
Stéphane Delaunay ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Metabolic Pathways

Heats of Reaction of Natural Rubber with Sulfur

1970 ◽  
Vol 43 (6) ◽  
pp. 1275-1293 ◽  
Author(s):  
N. Bekkedahl ◽  
J. J. Weeks
Keyword(s):  
Hydrogen Sulfide ◽  
Standard Deviation ◽  
Natural Rubber ◽  
Volume Change ◽  
Side Reaction ◽  
Enthalpy Change ◽  
Heat Of Reaction ◽  
Use Of Data ◽  
Heats Of Reaction

Abstract An adiabatic copper calorimeter was used to determine the heats of vulcanization of pale crepe natural rubber with sulfur for mixtures varying in composition from 0 to 32 per cent added sulfur. The side reaction that produces hydrogen sulfide was avoided by using reaction temperatures near 155° C. Heats of reaction at 25° C and at 155° C are reported. The enthalpy change at 25° C for compounds containing up to about 18 per cent sulfur is given in joules per gram of vulcanizate by the equation, ΔH25=−21.1·S with a standard deviation of 11 J/g. Here S is the percentage of combined sulfur. Above 18 per cent sulfur the heat of reaction at 25° C remains approximately constant at 380 ± 8 J/g. A comparison is made between the heat of vulcanization and the volume change on vulcanization, both as functions of combined sulfur, by making use of data in the literature.

scholarly journals CitI, a Transcription Factor Involved in Regulation of Citrate Metabolism in Lactic Acid Bacteria

2005 ◽  
Vol 187 (15) ◽  
pp. 5146-5155 ◽  
Author(s):  
Mauricio G. Martin ◽  
Christian Magni ◽  
Diego de Mendoza ◽  
Paloma López
Keyword(s):  
Transcription Factor ◽  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Rna Polymerase ◽  
Metabolic Pathways ◽  
Signal Propagation ◽  
Metabolic Energy ◽  
Citrate Metabolism ◽  
Divergent Gene ◽  
Dna Binding Affinity

ABSTRACT A large variety of lactic acid bacteria (LAB) can utilize citrate under fermentative conditions. Although much information concerning the metabolic pathways leading to citrate utilization by LAB has been gathered, the mechanisms regulating these pathways are obscure. In Weissella paramesenteroides (formerly called Leuconostoc paramesenteroides), transcription of the citMDEFCGRP citrate operon and the upstream divergent gene citI is induced by the presence of citrate in the medium. Although genetic experiments have suggested that CitI is a transcriptional activator whose activity can be modulated in response to citrate availability, specific details of the interaction between CitI and DNA remained unknown. In this study, we show that CitI recognizes two A+T-rich operator sites located between citI and citM and that the DNA-binding affinity of CitI is increased by citrate. Subsequently, this citrate signal propagation leads to the activation of the cit operon through an enhanced recruitment of RNA polymerase to its promoters. Our results indicate that the control of CitI by the cellular pools of citrate provides a mechanism for sensing the availability of citrate and adjusting the expression of the cit operon accordingly. In addition, this is the first reported example of a transcription factor directly functioning as a citrate-activated switch allowing the cell to optimize the generation of metabolic energy.

scholarly journals The recovery heat-production in oxygen after a series of muscle twitches

1928 ◽  
Vol 103 (723) ◽  
pp. 183-191 ◽  
Keyword(s):  
Lactic Acid ◽  
Heat Production

Experiments determining the recovery heat-production in oxygen after a short tetanic stimulus have been described on various occasions, e. g. , by Hartree and hill (1) (2) and by Hartree and Liljestrand (3). In employing the results of these experiments to calculate the "oxidative quotient for lactic acid" as defined by Meyerhof (see, for example (4). p. 567), viz.: (Lactic acid removed in recovery) / (Lactic acid-or carbohydrate equivalent-oxidised) a complication arises in respect of the anaerobic delayed heat (see 1, 5 and 6).

scholarly journals The heat-tension ratio in prolonged tetanic contractions

1931 ◽  
Vol 108 (759) ◽  
pp. 522-537 ◽  
Keyword(s):  
Lactic Acid ◽  
Heat Production ◽  
Acid Formation ◽  
The Absolute ◽  
Do So

It was found by Hartree and Hill (1921) that in tetanic contractions of various durations the relation between heat liberated and duration of stimulus soon becomes linear; from the slope of the curve relating the two variables the absolute values of the heat production were calculated, per centimetre length of muscle, per gramme weight of tension maintained, per second of stimulus, in contractions at various temperatures. No observations, however, were made with tetani longer than 2 seconds. The isometric time coefficients of lactic acid formation and of phosphagen breakdown (subsequently denoted, following Meyerhof, by the symbols K 2 ( I .) and K 2 ( P ) respectively) have been determined by various workers and summarised by Meyerhof (1930, pp. 102, 234, etc.). Recently, however, the existence of delayed lactic acid formation following a tetanus, long maintained by embden and his school, has been confirmed by Meyerhof and his collaborators (1931), who failed to do so in several previous investigations. Lundsgaard (1931) also has found that the anaerobic delayed lactic acid formation following a 5-second tetanus may be over one-half of the total lactic acid set free. When there is a delayed lactic acid formation amounting to as much as, or more than, 100 per cent. of that occurring during the contraction proper, it is obvious that the values of K 2 ( I .) and K 2 ( P ) lack significance unless the time from the end of the stimulus at which the chemical determinations are made is specified. The older chemical investigations mentioned thus require revision, which has been given in a recent paper by Meyerhof and Schulz (1931).

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