bluuebunny/crossref_metadata_2025 huggingface dataset:
THE EFFECT OF AUXINS ON PROTOPLASMIC STREAMING. III
Authors: Sweeney Beatrice Marcy , Thimann Kenneth V.
Published: May 2004

1. A new method is described which gives a continuous record of the absolute rate of protoplasmic streaming in epidermal cells of the Avena coleoptile.

2. With this method a study was made of the influence of malate and iodoacetate on streaming velocity, in order to make correlations with the previously established effects of these substances on growth and respiration.

3. In the presence of optimum concentrations of indole-3-acetic acid in freshly cut sections, malate had no effect on streaming. In the presence of very low concentrations of the auxin, however, malate increased the range of response, so that the threshold of auxin sensitivity was lowered some ten times by the malate. Malate alone had no effect on streaming.

4. In coleoptile sections, soaked overnight in sugar solution or in water, the acceleration of streaming normally caused by auxin almost disappears, but the presence of malate causes large accelerations of streaming by the auxin.

5. Similarly, in sections from old coleoptiles, which no longer show acceleration of streaming by auxin, the acceleration is restored when malate is added together with the auxin.

6. Malate does not enter the cell as rapidly as does auxin, but easily detectable amounts penetrate within 30 minutes.

7. Iodoacetate in the concentration which inhibits growth (5 x 10–5 M) completely inhibits the acceleration of streaming by auxin. In still lower concentrations iodoacetate slightly accelerates streaming. Higher concentrations, up to 2 x 10–4 M, did not reduce the rate of streaming below that of controls without auxin. The effect of iodoacetate is therefore to inhibit the acceleration caused by auxin and not to affect the basal streaming rate.

8. It is concluded that, just as for growth and respiration, malate is necessary for the response to auxin shown by acceleration of streaming. This further strengthens the triple parallel between the effects of auxin on streaming, growth, and respiration, all of which are apparently mediated by the 4-carbon acid system.
ACCUMULATION OF SALT AND PERMEABILITY IN PLANT CELLS
Authors: Hoagland D. R. , Broyer T. C.
Published: May 2004

1. Comparisons are made of concentrations of K and Br in exudates of barley roots and in expressed sap from roots, under conditions favorable for aerobic metabolism. Both methods lead to the same general viewpoint concerning metabolically governed transport of solutes by living plant cells.

2. Cyanide in low concentration prevented salt accumulation by barley roots. Methylene blue, without decrease of CO2 production by roots, destroyed power of salt accumulation.

3. K and Br ions entered roots to only a slight extent under an anaerobic condition, even with an inward gradient of ionic concentration.

4. Lactate or alcohol, under aerobic conditions, did not prevent rapid accumulation of salt by root cells.

5. Experiments on fluids obtained by suction from tomato roots gave evidence of loss of salt-accumulating power under the influence of N2 gas or CO2 gas, together with probable effects on cell permeability.

6. Several experiments on Nitella cells in which radioactive isotopes were used are reported. Bromide gradually moved into vacuolar sap until the concentration appeared to exceed that of the protoplasm, on the basis of the results of the several types of experiments. Accumulation of salt in the vacuole did not occur anaerobically.

7. Some views of interrelations of permeability, salt accumulation, and metabolism are suggested for further discussion.
FERMENTATIVE AND PHOTOCHEMICAL PRODUCTION OF HYDROGEN IN ALGAE
Authors: Gaffron Hans , Rubin Jack
Published: May 2004

1.. After 2 hours of fermentation in nitrogen the metabolism of those algae which were found capable of photoreduction with hydrogen changes in such a way that molecular hydrogen is released from the cell in addition to carbon dioxide.

2. The amount of hydrogen formed anaerobically in the dark depends on the amount of some unknown reserve substance in the cell. More hydrogen is formed in presence of added glucose, but no proportionality has been found between the amount of substrate added and that of hydrogen formed. This is probably due to the fact that two types of fermentation reactions exist, with little or no connection between them. Whereas mainly unknown organic acids are formed during the autofermentation, the addition of glucose causes a considerable increase in the production of lactic acid.

3. Algae which have been fermenting for several hours in the dark produce upon illumination free hydrogen at several times the rate observed in the dark, provided carbon dioxide is absent.

4. Certain concentrations of dinitrophenol strongly inhibit the evolution of hydrogen in the dark. Fermentation then continues mainly as a reaction leading to lactic acid. In such poisoned algae the photochemical liberation of hydrogen still continues.

5. If the algae are poisoned with dinitrophenol the presence of carbon dioxide will not interfere with the photochemical evolution of hydrogen.

6. The amount of hydrogen released in this new photochemical reaction depends on the presence of an unknown hydrogen donor in the cell; it can be increased by the addition of glucose but not in proportion to the amount added.

7. The results obtained allow for a more correct explanation of the anaerobic induction period previously described for Scenedesmus and similar algae. The possibility of a photochemical evolution of hydrogen had not been taken into account in the earlier experiments.

8. The origin of the hydrogen released under the influence of light is discussed.
SEDIMENTATION IN THE ANGLE CENTRIFUGE
Authors: Pickels Edward G.
Published: May 2004

1. Using hemocyanin from Limulus polyphemus as a test material, the process of sedimentation in the angle centrifuge, operating both in vacuum and in the open air, has been investigated.

2. Sedimentation in a given field of force was found less efficient when centrifugation was conducted in the open air, because of thermal convection.

3. Correlations have been made with results obtained in the analytical ultracentrifuge, and a theory of sedimentation in inclined tubes has been presented to explain the experimental results.

4. It has been shown that under proper conditions the angle centrifuge may be used for approximate determinations of particle size.

5. Recommendations, based mostly on experimental evidence, have been made for improving sedimentation and interpreting results.

6. To counteract convective disturbances of either thermal or inertial origin, a satisfactory method has been developed which consists of furnishing the fluid under study with a synthetic density gradient, formed with sucrose or some other non-sedimentable material.
THE ANTIPROTEOLYTIC ACTIVITY OF SERUM
Authors: Grob David
Published: May 2004

1. Heating diluted serum at 80° C. for 10 minutes made it a better medium for bacterial growth. This is believed to have been at least partly due to destruction of the serum antiprotease.

2. Growth was accelerated, and proceeded further, in the presence of trypsin.

3. Growth was somewhat retarded in the presence of pancreatic trypsin inhibitor.

4. The bacteriostatic action of sulfathiazole in serum was reduced by heating the serum at 80° C., and much more markedly (in any of the media studied) by adding trypsin. It was greater in serum and albumen than in peptone and meat infusion.

5. The significance of the experimental results was considered in relation to the possible influence of leucoprotease and of serum antiprotease on bacterial growth and sulfonamide action.
STUDIES ON THE MECHANISM OF HYDROGEN TRANSPORT IN ANIMAL TISSUES
Authors: Potter V. R. , Albaum H. G.
Published: May 2004

1. The effect of ribonuclease on various enzyme systems was studied as one approach to the problem of whether or not these enzymes are contained in macromolecules of ribonucleoprotein nature in protoplasm.

2. Ribonuclease inhibited CoI-cytochrome c reductase, succinic dehydrogenase, and cytochrome oxidase, all of which require cytochrome c in order to function. Ribonuclease did not act on cytochrome c.

3. Ribonuclease did not inhibit urease, xanthine oxidase, catalase, alkaline phosphatase, or adenosine triphosphatase under the conditions employed.

4. It was suggested that ribonuclease acted sterically by preventing contact between cytochrome c and its activating centers.

5. It was suggested that the enzymes inhibited may be contained in a ribonucleoprotein of macromolecular dimensions but that the enzymes not inhibited are not necessarily excluded from such a complex by the data presented.

6. Further evidence against the Szent-Györgyi theory of hydrogen transport was presented and discussed.
PHYSICAL PROPERTIES OF THE ALLANTOIC AND AMNIOTIC FLUIDS OF THE CHICK
Authors: Walker Paul Andrew
Published: May 2004

1. The hydrogen ion concentration of the allantoic and amniotic fluids of the developing chick has been determined over the period of incubation between the 7th and 19th days using the glass electrode technique.

2. Changes in this property have been related to changes in the chemical composition of these two fluids.

3. The results of this investigation have been compared with those obtained by other workers. Excellent confirmation has been afforded the work of Yamada, whereas the work of Aggazzotti, which has long been accepted, is shown to be in error.
AN EXPERIMENTAL SEPARATION OF OXYGEN LIBERATION FROM CARBON DIOXIDE FIXATION IN PHOTOSYNTHESIS BY CHLORELLA
Authors: Fan C. S. , Stauffer J. F. , Umbreit W. W.
Published: May 2004

Using intact cells of Chlorella pyrenoidosa it is possible to obtain oxygen by the reduction of certain reducible materials other than carbon dioxide. Of these, benzaldehyde was studied in some detail. This reduction does not involve the production of carbon dioxide from the benzaldehyde. Stoichiometrical relationships as expressed by the following equation:

2C6H5CHO + 2H2O → 2C6H5CH2OH + O2 are somewhat difficult to obtain because the benzaldehyde can disappear from the reaction mixtures by dark reactions. The technique is now available which permits detailed studies of the oxygen-liberating mechanisms in photosynthesis.
PHYSICAL PROPERTIES OF THE ALLANTOIC AND AMNIOTIC FLUIDS OF THE CHICK
Authors: Walker Paul Andrew
Published: May 2004

The study of the changes occurring during incubation in the surface tension of the two extra-embryonic fluids of the hen's egg has yielded results which in part harmonize with previous studies of the chemical and physical nature of these liquids, and which in part are quite inexplicable in the light of these investigations. The necessity for a more thorough chemical analysis of these fluids is clearly indicated before any exact evaluation of their significance to the developing embryo can be made.
ON THE INACTIVATION OF ASCORBIC ACID OXIDASE
Authors: Powers Wendell H. , Dawson Charles R.
Published: May 2004

1. In the absence of protective agents, highly purified ascorbic acid oxidase is rapidly inactivated during the enzymatic oxidation of ascorbic acid under optimum experimental conditions. This inactivation, called reaction inactivation to distinguish it from the loss in enzyme activity that frequently occurs in diluted solutions of the oxidase prior to the reaction, is indicated by incomplete oxidation of the ascorbic acid as measured by oxygen uptake; i.e., "inactivation totals."

2. A minor portion of the reaction inactivation appears to be due to environmental factors such as rate of shaking of the manometers, pH of the system, substrate concentration, and oxidase concentration. The presence of inert protein (gelatin) in the system ameliorates the environmental inactivation to a considerable extent, and variation of the above factors in the presence of gelatin has much less effect on the inactivation totals than in the absence of gelatin.

3. A major portion of the reaction inactivation of the oxidase appears to be due to some factor inherent in the ascorbic acid-ascorbic acid oxidase-oxygen system, possibly a highly reactive "redox" form of oxygen other than H2O2 or H2O. The inactivation cannot be attributed to dehydroascorbic acid, the oxidation product of ascorbic acid.

4. Small amounts of native catalase, native peroxidase, native or denatured methemoglobin, and hemin when added to the system, markedly protect the oxidase against inactivation. Cytochrome c has no such protective action. Likewise proteins such as egg albumin, gelatin, denatured catalase, or denatured peroxidase show no such protective action.

5. None of the protective agents mentioned above affect the initial rate of oxygen uptake or change the total oxygen absorbed for complete oxidation of the ascorbic acid, and hence do not act by removal of hydrogen peroxide, per se.

6. Sodium azide and hydroxylamine hydrochloride which inhibit catalase and peroxidase activity also inhibit the protective action of these iron-porphyrin enzymes.
THE OSMOTIC BEHAVIOR OF CRENATED RED CELLS
Authors: Ponder Eric
Published: May 2004

The anomalously small swelling which the red cells of human oxalated blood undergo in hypotonic plasma is related to the extent to which the cells are crenated. Reasons are given for regarding crenation as corresponding to gelation, and the bulk modulus for crenated cells, calculated from the measurements of swelling in hypotonic plasma, is shown to be of the same order as that for gelatin gels.
THE STRUCTURE OF THE COLLODION MEMBRANE AND ITS ELECTRICAL BEHAVIOR
Authors: Sollner Karl , Beck Paul W.
Published: May 2004

1. Dried collodion membranes are known to swell in water and to the same limited extent also in solutions of strong inorganic electrolytes (Carr and Sollner). The present investigation shows that in solutions of organic electrolytes and non-electrolytes, the swelling of dried collodion membranes is not as uniform, but depends on the nature of the solute.

2. The solutions of typically "hydrophilic" substances, e.g., glycerine, glucose, and citric acid, swell collodion membranes only to the same extent as water and solutions of strong electrolytes.

In solutions of typically carbophilic substances (e.g., butyric acid, valeric acid, isobutyl alcohol, valeramide, phenol, and m-nitrophenol) the swelling of the membranes is much stronger than in water, according to the concentration used. For the brand of collodion used the swelling in 0.5 M solution was in some cases as high as 26 per cent of the original volume, as compared to 6 to 7 per cent in water. Therefore, in these solutions the "water-wetted dried" collodion membrane is not rigid, inert, and non-swelling, but behaves as a swelling membrane.

3. The solutes which cause an increased swelling of the membranes are accumulated in the latter, the degree of accumulation being markedly parallel with the degree of their specific swelling action.

4. The anomalously high permeabilities of certain carbophilic organic solutes reported by Michaelis, Collander, and Höber find an explanation in the specific interaction of these substances with collodion.

5. The use of the collodion membrane as a model of the ideal porous membrane is restricted to those instances in which no specific interaction occurs between the solute and the collodion.
THE EFFECTS OF URETHANE AND CHLORAL HYDRATE ON OXYGEN CONSUMPTION AND CELL DIVISION IN THE EGG OF THE SEA URCHIN, ARBACIA PUNCTULATA
Authors: Fisher Kenneth C. , Henry R. J.
Published: May 2004

The effects of a series of concentrations of the narcotics, ethyl carbamate and chloral hydrate, have been determined on the consumption of oxygen by fertilized and unfertilized eggs of the sea urchin Arbacia punctulata. In the fertilized eggs the effects of the two inhibitors on cell division were also examined. The following observations were made:

1. Assuming that the narcotic acts upon a single catalyst in the unfertilized egg the degree to which the consumption of oxygen is inhibited in this resting cell can be related to the narcotic concentration by an expression derived from the law of mass action.

2. To account for the relation between the concentration of the narcotic and its effect on respiration in the fertilized eggs, it is necessary to conclude that in them the narcotic acts on two parallel respiratory systems. The experimental data can be quantitatively predicted (1) if the reaction of the narcotic on the two systems is governed by the law of mass action and (2) if 40 per cent of the oxygen consumption is mediated by one system, the "activity" system, and the remainder by the other, the "resting" or "basal" system.

3. The mass law constants applying to the resting system in the fertilized egg are similar to those for the single system functioning in the unfertilized egg so that these two respiratory systems are probably identical.

4. The concentrations of the narcotics just sufficient to abolish cell division affect primarily the activity system, the existence of which was inferred from the respiratory experiments. It is concluded that normal cell division requires specifically the normal function of the activity system, that in fact the energy for cell division is made available through that system.
DIFFERING RATES OF DEATH AT INNER AND OUTER SURFACES OF THE PROTOPLASM
Authors: Osterhout W. J. V.
Published: May 2004

A previous paper showed that when the inner protoplasmic surface has lost its potential under the influence of formaldehyde the outer surface can still respond to changes in the concentration of electrolytes.

The present paper indicates that after the inner surface has lost its potential there may be a sudden development of negative potential at the outer surface due to substances coming out of the sap and combining with formaldehyde.
A SELECTIVE LETHAL EFFECT OF PENICILLIN ON SARCOMA CELLS GROWING WITH NORMAL TISSUE IN ROLLER TUBE CULTURES
Authors: Cornman Ivor
Published: May 2004

An agent present in pharmaceutical Squibb and in Reichel penicillin preparations was found to exert a selective lethal effect upon rat and mouse sarcoma cells growing with normal cells in tissue cultures.
NATURE OF THE GROWTH FACTOR FOR THE COLORLESS ALGA PROTOTHECA ZOPFII
Authors: Anderson Edward H.
Published: May 2004

Barker's study on the nutritive requirements of Prototheca zopfii indicated that this colorless alga fails to grow in the absence of small amounts of yeast extract. A study of the growth factor requirements of Prototheca has shown that the active constituent of yeast extract necessary for the growth of this organism is thiamin (vitamin B1). Thiamin can fully replace the complex yeast material and allows, in the basal medium used, a maximum cell yield in concentrations of 1–3 x 10–7 M.

Thiamin as such, however, is not essential for the growth of Prototheca zopfii. The alga can develop equally well if supplied with both the thiazole and pyrimidine constituents of this vitamin. These appear to be needed in equimolar proportions. Maximum cell yield is obtained with 3 x 10–8 M concentrations of the two components.
MAXIMA IN RATE-CONCENTRATION CURVES AND THEIR RELATION TO THE STRUCTURAL ASPECTS OF CELLULAR METABOLISM
Authors: Spiegelman S. , Reiner J. M.
Published: May 2004

1. Reproducible maxima are exhibited in the rate-concentration curves obtained by studying the effects of ethyl- and phenylurethanes on regeneration rates of hydranths in Tubularia.

2. The general problem of maxima in rate-concentration curves is analyzed in terms of reaction kinetics of relatively simple systems.

3. Certain systems were shown to exhibit this phenomenon. A comparison is made of these with similar ones which fail to do so.

4. The possible rôle in this phenomenon of cellular structure and its attendant geometrical constraints is discussed in terms of the above comparison.
EFFECTS OF HYDROXYL ON NEGATIVE AND POSITIVE CELLS OF NITELLA
Authors: Osterhout W. J. V.
Published: May 2004

Remarkable changes are brought about by KOH in transforming negative cells of Nitella (showing dilute solution negative with KOH) to positive cells (showing dilute solution positive with KOH). NaOH is less effective as a transforming agent.

This might be explained on the ground that the protoplasm contains an acid (possibly a fatty acid) which makes the cell negative and which is dissolved out more rapidly by KOH than by NaOH, as happens with the fatty acids in ordinary soaps.

Part of a negative cell can be changed to positive by exposure to KOH while the untreated portion remains negative.

After exposure to KOH the potential the protoplasm has when in contact with NaCl may increase. At the same time there may be an increase in the potassium effect; i.e., in the change of P.D. in a positive direction observed when 0.01 M KCl is replaced by 0.01 M NaCl.

In some cases the order of ionic mobilities is uK > vOH > uNa. This shows that the protoplasmic surface cannot be a pore system: for in such a system all cations must have greater mobilities than all anions or vice versa.
SOME PROPERTIES OF PROTOPLASMIC GELS
Authors: Osterhout W. J. V.
Published: May 2004

The chloroplast of Spirogyra is a long, spirally coiled ribbon which may contract to form a short, nearly straight rod. This happens under natural conditions and it can also be produced by a variety of inorganic salts and by some organic substances.

It also occurs when the chloroplast is freed by centrifugal force from the clear peripheral protoplasm which is in contact with the cellulose wall. It would therefore seem that the chloroplast may be passively stretched by the action of the clear protoplasm and hence it contracts as soon as it is set free. This contraction happens in dead as well as in living cells.

It would be of much interest to know how the protoplasm brings about the coiling of the chloroplast and how the chloroplast is set free by various reagents. Presumably they must penetrate the living protoplasm to produce the effects described.

In one species partial contraction without detachment from the peripheral protoplasm can be brought about by lead acetate. This is reversible. Lead nitrate does not produce this result.

The attack upon the problem is greatly facilitated by the study of dead cells. Thereby we reduce the number of variables but the chloroplast continues to react to certain chemical and physical agents in much the same manner as in the living cell and the solution surrounding it can be controlled as is not possible in the living cell.

We must await further investigation to learn what plant and animal cells contain gels under tension and what functions they perform.
THE MECHANISM OF THE INHIBITION OF HEMOLYSIS
Authors: Ponder Eric
Published: May 2004

This paper is concerned with hemolytic systems containing sodium taurocholate, sodium glycocholate, or saponin, and either human red cells or the ghosts (stromata) of human red cells. The lysins are allowed to react with the cells for a short time (1 minute or less), and with the ghosts for a long time (4 hours), and the quantity of lysin remaining in the bulk phase, after the removal of the cells or of the ghosts, is found by (a) colorimetric methods, and (b) methods which measure its hemolytic activity.

In the experiments in which the lysins react with the cells for a time so short that none of them is hemolyzed, it is found: (1) that the suspension medium of a cell suspension contains inhibitory substances which render a small amount of the lysin non-lytic, (2) that on the addition of the lysin to the cell suspension, a further and much larger amount of lysin is rendered non-lytic, and (3) that the quantity of chromogenic material in the bulk phase, after the lysin has been in contact with the cells and the latter have been removed, is substantially the same as that initially present. No appreciable quantity of lysin, accordingly, accumulates in increased concentration at the cell surfaces. The results of the colorimetric determinations show that the apparent disappearance of lysin from the bulk phase, once thought to be due to an accumulation of lysin at the cell surfaces, is the result either of an inhibitory process or of a sudden utilization of lysin unrecognized by existing theory.

In the experiments in which the lysins react with stromata for 4 hours, it is found: (1) that the suspension medium of a stroma suspension contains inhibitory substances which render some of the lysin non-lytic, (2) that when the lysin reacts with the stromata over a period of time, a much greater quantity of lysin is rendered non-lytic, and (3) that the concentration of chromogenic material in the bulk phase of the lysin-stroma system, after 4 hours of reaction, is substantially the same as it was initially. The observations can be accounted for by supposing that the lysin molecules are as chromogenic after reacting with the cell components as before, and by their not being bound to the cell or to the ghost, but diffusing back, combined with the components with which they have reacted, into the bulk phase. Such a process would have similarities to the process of penetration and breakdown of mixed protein-lipoid films. Because it is not possible at present to decide how much of the lysin is rendered inert because of utilization in a reaction with cell components, and how much because of the effect of inhibitory substances, difficulties and uncertainties arise in connection with the expressions which have been used to describe the kinetics of hemolysis.
PROTEOLYTIC ENZYMES
Authors: Grob David
Published: May 2004

1. The literature on conditions affecting the activity of proteolytic enzymes has been reviewed.

2. Experimental data on the control of the activity of trypsin, leucoprotease, papain, serum antiprotease, leucopeptidase, and pancreatic peptidase have been presented. These data indicate that:

(a) The polymorphonuclearleucocytes of the cat contain abundant proteinase and peptidase active at neutral pH; those of the rabbit lack proteinase active at neutral pH.

(b) Reducing agents, including several biologically important thiol-sulfhydryl compounds and ascorbic acid, inhibit the activity of leucoprotease and trypsin. For each reductant the degree of inhibition is proportional to the reducing capacity of the medium.

(c) p-Aminobenzoic acid, sulfonamides (especially sulfathiazole), and many diphenyl sulfones inhibit the activity of leucoprotease.

(d) Serum, plasma, several heavy metals, ammonium salts, asparagine, thiourea, heparin, glutamic acid, tyrothricin, calcium chloride, and bile salts and bile acids also inhibit the activity of leucoprotease, and in most cases of trypsin too.

(e) Preparations of tryptic digests of proteins, and egg white trypsin inhibitor, inhibit trypsin to a much greater degree than leucoprotease.

(f) Mild oxidizing agents increase the activity of leucoprotease and trypsin.

(g) Oxidizing agents and some inhibitors of sulfhydryl groups inhibit the antiproteolytic activity of the serum. It is suggested that serum antiprotease may consist (chiefly) of reducing agents, including thiol-sulfhydryl peptides which exert their antiproteolytic activity by virtue of the presence of sulfhydryl groups.

(h) The antiproteolytic activity of the serum is progressively weakened by exposure to a hydrogen ion concentration below pH 6.5 or above pH 9.7. Because of this the pH optima of leucoprotease and trypsin are shifted in the presence of serum from pH of 7 and 8 to pH of 6 to 6.5, and the range of activity of these enzymes is slightly widened, in both acid and alkaline reactions.

(i) Reducing agents increase the activity of leucopeptidase and pancreatic peptidase. Serum, sulfathiazole, and thiourea have little or no effect.

3. The significance of the oxidation-reduction system in the control of the activity of leucoprotease, trypsin, serum antiprotease, leucopeptidase, and pancreatic peptidase has been emphasized.
PROTEOLYTIC ENZYMES
Authors: Grob David
Published: May 2004

It has been suggested that the ability to control the activity of leucoprotease and serum antiprotease may prove useful in the further study and understanding of such phenomena as: (1) inflammation; (2) the resolution of inflammatory exudates and the absorption of absorbable foreign bodies; (3) the protection of joint and other structures from the proteolytic action of leucoprotease; (4) the neutralization of the destructive protease liberated in acute pancreatitis and from duodenal fistulae; (5) experimental arteriosclerosis and arteriolonecrosis; (6) the coagulation of the blood; (7) the possibility of prolonging the action of insulin; (8) the release of thyroglobulin by the thyroid gland; (9) bacterial growth and sulfonamide action.

In this last respect evidence has been presented that the products of the hydrolysis of protein by leucoprotease stimulate bacterial growth and directly and indirectly inhibit sulfonamide action, and the hope has been expressed that the ability to control leucoprotease action may contribute to the more successful use of chemotherapeutic agents in purulent lesions.
THE CHEMISTRY OF DAYLIGHT VISION
Authors: Bliss Alfred Frederick
Published: May 2004

1. While several reports of photosensitive pigments from the retinas of animals possessing large numbers of cone cells have been published, the only study which could be confirmed was Wald's discovery of iodopsin, a red-sensitive pigment from chicken eyes.

2. In its chemical properties, such as the range of pH stability and the effect of polar organic solvents, iodopsin resembles rhodopsin but is considerably more labile.

3. A partial purification from inert yellow impurities has been effected by prehardening the retinas in pH 4.9 acetate buffer before extraction by 2 per cent digitonin. Rhodopsin was an inevitable contaminant in most methods of extraction, but could be reduced to about 10 per cent of the absorption due to iodopsin by extraction of unhardened retinas with 4 per cent Merck's saponin in ¾ saturated magnesium sulfate for about 1 hour.

4. The rate of bleaching of iodopsin was found to be first order and linear with respect to energy.

5. The bleaching effectiveness spectrum of iodopsin was determined with the aid of color filters of known energy transmission, and shows a maximum at 560 mµ in the yellow green with a lower plateau in the blue. The spectrum is in good agreement with the sensitivity of the human cones except for the wavelength of maximum bleaching effectiveness. The maximum sensitivity of the human cones is found at 540 mµ.

6. Previous reports of changes in pH and inorganic phosphate level of retinas due to bleaching could not be confirmed.
THE POTENTIOMETRIC ANALYSIS OF MEMBRANE STRUCTURE AND ITS APPLICATION TO LIVING ANIMAL MEMBRANES
Authors: Meyer Kurt H. , Bernfeld P.
Published: May 2004

1. The electromotive forces which arise, if two electrolyte solutions are separated from each other by a layer of any kind, are discussed. A general equation is derived comprising the known equations for diffusion, partition, and membrane (Donnan) potentials as special cases.

2. A method is proposed to analyse membranes potentiometrically with respect to their cation or anion selectivity, their dissolving power for ions, and their influence on ion mobility (migration velocity).

3. The possibility of analysing a membrane composed of several layers of different permeability is discussed.

4. The investigation of the skin of the belly of Rana temporaria leads to the following results. It is composed of at least four layers of different permeability, one of which is specifically permeable to H ions and is very likely identical with the "basal membrane" situated between the stratum germinativum and the corium. The major part of the resting potential of the skin is located across this membrane and is due to the difference of H+ concentrations on both sides of the membrane.

5. Experiments on muscle show that the sarcolemma is specifically permeable to H ions. The injury potential of the muscle is attributed to the difference of H+ concentration inside and outside the fibre.
HEMOLYTIC SYSTEMS CONTAINING ANIONIC DETERGENTS
Authors: Ponder Eric
Published: May 2004

1. The members of the homologous series of anionic detergents, the sodium salts of the sulfated straight chain alcohols with the general formula CnH2n+1·SO3·Na, are hemolytic, the lytic activity being at a maximum when the compound contains 14 carbon atoms in the chain. In systems in which lysis is comparatively rapid, the hemolytic effect increases with increasing pH, but in systems containing quantities of lysin near the asymptotic concentrations the pH dependence of the activity is reversed. The effect of temperature is principally one on the velocity constant of the lytic reaction, with smaller effects on the position of the asymptotes of the time-dilution curves and on their shape.

2. The quantities of the detergents which produce disk-sphere transformations are approximately one-tenth of those required to produce complete hemolysis. In most cases, the shape change occurs when there are too few detergent molecules present to cover the red cell surfaces with a monolayer.

3. Plasma inhibits the hemolytic action of these detergents, and, in the quantities in which they occur in plasma, lecithin, serum globulin, cholesterol, and serum albumin, produce inhibitory effects which increase in that order in systems containing the C-14 sulfate. It can be inferred from these inhibitory effects that the anionic detergents can form compounds or complexes with lipid, lipoprotein, and protein components of the red cell ultrastructure.
THE PYRUVATE METABOLISM OF SEA URCHIN EGGS DURING THE PROCESS OF CELL DIVISION
Authors: Goldiger James M. , Barron E. S. Guzman
Published: May 2004

The eggs of Arbacia and starfish contained about 70 and 25 micrograms of pyruvate per gm. of dry cells respectively. Arbacia eggs utilized added pyruvate, although the O2 uptake did not increase. On fertilization the utilization of pyruvate increased sevenfold. This pyruvate seems to be metabolized, as in other cells, with diphosphothiamine as coenzyme. The diphosphothiamine content of fertilized and non-fertilized eggs was about 16 micrograms; that of sperm, 30 micrograms. Penetration of sperm into the egg and fertilization with cell division to the pluteus stage did not bring forth appearance of succino-dehydrogenase. The possible mechanism of fertilization and cell division is discussed.
THE NUCLEOPROTAMINE OF TROUT SPERM
Authors: Pollister A. W. , Mirsky A. E.
Published: May 2004

The nucleoprotamine of trout sperm can be extracted completely with 1 M sodium chloride. On reducing the salt concentration to 0.14 M, physiological saline, the nucleoprotamine precipitates in long, fibrous strands. When the nucleoprotamine, dissolved in M NaCl, is dialyzed all the protamine diffuses through the membrane leaving behind highly polymerized, protein-free desoxyribose nucleic acid. The nucleoprotamine constitutes 91 per cent of the lipid-free mass of the sperm nucleus. While nucleoprotamine is being extracted by M NaCl a stage is reached at which the sperm chromosomes are clearly visible.
CRYSTALLIZATION OF PEPSIN FROM ALCOHOL
Authors: Northrop John H.
Published: May 2004

1. Pepsin is soluble in 65 per cent alcohol and may be readily crystallized from 20 per cent alcohol. The crystals appear as needles or plates which may be transformed into the usual hexagonal bipyramids by recrystallization from water. The different crystals are probably two crystalline forms of the same chemical substance.

2. The enzyme is quite stable in 20 per cent alcohol at pH 2.0 but is inactivated by high concentrations of alcohol.

3. The enzyme is stable for several hours in 65 per cent alcohol at pH 4.0 to 5.0 but is rapidly inactivated in more acid solution.

4. No increase in activity could be noted after treatment with hydrogen peroxide.

5. No proteolytic activity either before or after treatment with hydrogen peroxide could be found in trichloracetic acid filtrates, butyl alcohol extracts of pepsin preparations, or oxidized phenylhydrazine solutions.
REACTION OF ENZYMES AND PROTEINS WITH MUSTARD GAS (BIS(ß-CHLOROETHYL)SULFIDE)
Authors: Herriott Roger M. , Anson M. L. , Northrop John H.
Published: May 2004

1. The rate of reaction of mustard gas (H) with thirteen proteins has been determined. The extreme variation in reaction rates is about 100:1.

2. No qualitative difference in the results was observed when the treatment with H was carried out by the Dixon or stirring methods.

3. The kinetics have been analyzed and a bimolecular equation derived which fits the facts.

4. The carboxyl groups of all proteins reacted when the reaction with H was carried out at pH 6.0 in M/25 acetate buffer. In most cases the number of carboxyl groups covered was approximately equal to the number of H residues bound.

5. The amino groups of proteins failed to react with the possible exception of yeast hexokinase.

6. The color obtained when proteins were mixed with Folin's phenol reagent at pH 8.0 decreased as the protein was treated with H. The color returned on treatment of the H-protein with alkali and many of the combined H groups were hydrolyzed. Similar results were observed when a concentrated glycyltyrosine solution was treated with H.
REJECTION THRESHOLDS OF THE BLOWFLY FOR A SERIES OF ALIPHATIC ALCOHOLS
Authors: Dethier V. G. , Chadwick L. E.
Published: May 2004

Series of concentrations of 15 aliphatic alcohols were presented in 0.1 M sucrose to the tarsi of antennectomized-labellectomized blowflies (Phormia regina Meigen). With the pri-n-alcohols the mean concentrations at rejection formed a Traube series. When the rejection thresholds for all the alcohols tested were compared with their boiling points, vapor pressures, molecular surface areas) molecular moments, water-cottonseed oil distribution coefficients, standard free energies, and activity coefficients, a very high degree of correlation was found in each case. It is concluded that the limiting process which was measured is concerned with the receptor cells rather than with some other element in the complex response. Stimulative power was evidently not dependent on osmotic pressure nor on rate of molecular diffusion in solution, and the correlation with vapor pressure was inverse. It is judged that surface energy relationships are concerned in stimulation, but the exact mechanism cannot be defined until more is known about the structure of the sensory surface and about the process of excitation. The physiological activity of the alcohols is related more closely to the ease with which they gain access to the cell than to their chemical interaction with cellular constituents.
THE RELATIONSHIP BETWEEN CHEMICAL STRUCTURE AND THE RESPONSE OF BLOWFLIES TO TARSAL STIMULATION BY ALIPHATIC ACIDS
Authors: Chadwick L. E. , Dethier V. G.
Published: May 2004

Using the technique of proboscis extension in antennectomized-labellectomized flies, the rejection thresholds of Phormia regina for 18 fatty acids and one mineral acid have been determined.

The conclusions reached on the basis of these data may be summarized in the following terms:

Tarsal stimulation by acids involves the summation of components from at least two sources. Of these the hydrogen ion is the most important. The other major factor is probably the anion rather than the undissociated acid. The stimulating power of the anions (or free acid molecules) increases with increasing chain length in both the mono- and dicarboxylic series, but the rate of increase decreases as the series is ascended. Acids containing 6 or more carbon atoms are not sufficiently soluble in 0.1 M sucrose to reach the threshold of rejection. Substitution of —H in the acyl grouping by —Cl, —OH, =O or —COOH, the presence of a C=C bond, or a shift from the trans- to the cis- configuration all diminish the effectiveness of the anion (or free acid). But since such alterations also augment the degree of dissociation and consequently the concentration of hydrogen ions, the net result is ordinarily a lowering of threshold in terms of the molar concentration required for rejection.
THE EFFECTS OF SULFATHIAZOLE AND OF PROPYL CARBAMATE ON THE RATE OF OXYGEN CONSUMPTION AND GROWTH IN ESCHERICHIA COLI
Authors: Fisher Kenneth C. , Armstrong Florence H.
Published: May 2004

1. The rates of growth and of oxygen consumption by cells of E. coli have been measured under identical conditions, and the effects of sulfathiazole (ST) and of n-propyl carbamate (PC) on these two processes have been compared.

2. The rate of growth was measured by (a) the increase in the viable cell count, (b) the increase in the optical density of the culture, (c) the increase in the rate of oxygen consumption, and (d) the decrease in the ammonia of the medium. The results as indicated by these several measures were identical under the conditions of these experiments.

3. Concentrations of ST or of PC which are just sufficient to stop growth completely, lower the rate of oxygen consumption per unit of bacterial protoplasm to a value approximately 50 per cent of that seen in the absence of the inhibitor.

4. It is shown that the rate of oxygen consumption in cells from old cultures is less affected by ST than is the rate of oxygen consumption by cells from young cultures. It is probable that the rate of oxygen consumption by "old" cells is lower than that of "young" cells.

5. The effects of ST and PC on both the rate of oxygen consumption and the rate of growth are very similar, indicating in a general way, that the mechanism of the actions of these two inhibitors is similar. Furthermore, since both of them produce appreciable inhibition of the rate of oxygen consumption while they are inhibiting growth, the possibility that the effect on oxygen consumption is the immediate cause of the effect on growth must be entertained.
ISOLATION OF A CRYSTALLINE PROTEIN COMPOUND OF TRYPSIN AND OF SOYBEAN TRYPSIN-INHIBITOR
Authors: Kunitz M.
Published: May 2004

A crystalline protein compound has been isolated from a solution containing crystalline trypsin and crystalline soybean inhibitor. The protein consists of about equal weights of trypsin and of the inhibitor. Denaturation by heat or by alkali resolves the compound into its components.
THE EFFECTS OF SERUM ON SPERMATOZOA
Authors: Chang M. C.
Published: May 2004

A spermicidal factor was found in fresh human, bovine, rabbit, guinea pig, and rat sera. It kills the spermatozoa of its own species (except in the case of human serum) and the sperms of other species. It was unstable, thermolabile, and of large molecular size. It was present in limited quantity in the fresh serum and could be used up by a definite number of spermatozoa. It could be destroyed by sodium citrate, by Seitz filtration, by trypsin, and by snake venom. This factor was not present in tissue extracts and various plasma protein fractions. The strength or concentration of this factor varies in different individuals and in different species. This factor has several characteristics similar to those of complement.
K-Na EXCHANGE ACCOMPANYING THE PROLYTIC LOSS OF K FROM HUMAN RED CELLS
Authors: Ponder Eric
Published: May 2004

In systems containing human red cells and sodium taurocholate as a lysin, or distearyl lecithin as a sphering agent, the prolytic loss of K at 25°C. is accompanied by a gain of Na by the cell, the gain being somewhat greater than the K loss. A small volume increase accompanies the exchange. The kinetics of the K loss and the Na gain are similar to those already described; i.e., the changes are rapid at first, and slow down so that after 12 to 20 hours it appears that a new steady state is being approached.

Similar, but smaller, losses of K and gains of Na occur when the cells stand in isotonic NaCl at 25°C. without the addition of a lysin or sphering agent.

On these and other experimental grounds, it is impossible to retain the idea that the mammalian red cell in general is impermeable to cations. The cells nevertheless seem to be in a steady state with respect to their environment, their ionic composition changing as the composition of the environment is changed. The possible processes by means of which one steady state can be exchanged for another—changes in the permeability of a surface membrane, changes in the velocity of an active ion transfer process dependent on red cell metabolism, and changes in the activity of the ions in the red cell interior as a result of changes in an orderly internal structure—are discussed.
A STUDY OF THE ADENOSINE TRIPHOSPHATASE ACTIVITY OF MYOSIN AND ACTOMYOSIN
Authors: Mommaerts W. F. H. M. , Seraidarian Krikor
Published: May 2004

1. An experimental study was made on the adenosine triphosphatase action of crystalline myosin and actomyosin preparations under different conditions.

2. No enzymatic activity was found in the absence of salts. Activation was given by KCl and CaCl2, whereas MgCl2 in the presence of other ions inhibited.

3. The effect of pH is complex. In stabilizing buffers or at low temperature, there are two optima (pH 6.2 to 6.5 and pH 9.2) provided Ca is present. Without Ca only the acid optimum is found. The highest activities are reached in glycine buffer at pH 9.2 in the presence of Ca.

4. The study of the Mg-Ca antagonism revealed that the inhibition due to Mg is fully developed with Mg:Ca ratios less than 1, the inhibition usually exceeding 90 per cent.

5. It is shown that in the muscle the myosin-ATPase is most probably also subjected to the inhibitory action of the Mg ions.

6. From data in the literature it is calculated that the liberation of inorganic phosphate during muscular activity takes place at a rate of at least 0.200 mg. P per mg. myosin per minute.

7. From the results of the present study it is found that the myosin in the muscle can liberate inorganic phosphate from ATP at a rate of at most 0.003 mg. P per mg. myosin per minute.

8. It is concluded therefore that myosin-ATPase cannot be responsible for the liberation of the main part of the phosphate in contracting muscle, and therefore cannot have the rôle in muscular metabolism ascribed to it in recent hypotheses and discussions.
SOLUBILITY OF MUSTARD GAS [BIS (ß-CHLOROETHYL) SULFIDE] IN WATER, MOLAR SODIUM CHLORIDE, AND IN SOLUTIONS OF DETERGENTS
Authors: Herriott Roger M.
Published: May 2004

1. The solubility of mustard (H) in water and in molar sodium chloride was found to be 5.8 x 10–3 molar and 3.2 x 10–3 molar respectively or 0.92 mg. per ml. and 0.5 mg. per ml. Solubility curves have been drawn and the usefulness of this method in examining the homogeneity of H preparations as well as in establishing their solubility, is discussed.

2. Certain detergents increase the solubility of H in water. The solubility was found to increase with the concentration of detergent.

3. Many detergents were found to affect the interfacial tension between H and water so that with slight agitation liquid H breaks up into minute droplets. This in turn greatly accelerates the rate of solution.
DETECTION OF MUSTARD GAS (H), LEWISITE (L), ETHYLDICHLORARSINE (ED), AND PHENYLDICHLORARSINE (PD) WITH TRAINED DOGS OR RATS
Authors: Northrop John H.
Published: May 2004

Dogs and rats may be trained to detect very low concentrations of mustard gas (0.1 gamma per liter of air) by shocking the animals with an induction coil when they touch meat which has been exposed to the gas.

Animals trained in this way will refuse meat which is contaminated with the gas.