Occurrence of inducible and NAD(P)-independent primary alcohol dehydrogenases in an alkane-oxidizingPseudomonas

Pseudomonas aeruginosa (strain 473) constitutively contains a soluble NADP-linked dehydrogenase active towards primary alcohols. In addition, at least two NAD(P)-independent primary alcohol dehydrogenases can be induced by growing this strain on primary alcohols,α,ω-diols orn-alkanes. These inducible enzymes were found to be bound to cellular structures. They reduce bovine cytochromec and various dyes, but not oxygen. The main difference between the inducible enzymes is their different capacity to oxidize ethanol. Noteworthy properties of the enzymes are:

1. the affinities for the straight-chain primary alcohols increase with increasing chain length (tested up to 1-decanol);
2. the affinities decrease when polar atoms or groups are introduced into the alcohol molecule;
3. enzyme preparations as well as intact cells, when provided with a mixture of alcohols, first oxidize the compound with the lowest solubility in water.

These properties can be explained by assuming that hydrophobic bonds are formed between the enzyme and aliphatic parts of the alcohol molecule.     

A study of the relationship between mechanical characteristics and the coastal vegetation among several broad-leaf trees in Miura Peninsula in Japan

The mechanical properties of broad-leaf tree species in a maritime-wind exposed habitat in central Japan were examined. The broad-leaf trees studied were Celtis sinensis var. japonica, Ilex integra, Eurya japonica, Pittosporum tobira, Euonymus japonicus and Cinnamomum japonicum. The results obtained can be summarized briefly as follows:

1. At places with weaker wind, the number of species increased and the height of the canopy increased.
2. The fracture strength σ_m showed no dependence on tree part or branch thickness, but was constant.
3. The order of strength was Celtis sinensis var. japonica > Ilex integra > Eurya japonica > Pittosporum tobira > Euonymus japonicus > Cinnamomum japonicum, and these six species could best adapt to the wind pressure in the study area.
4. Within species, fracture strength varied directly with wind strength.
5. The strain ε_m decreased as the trunk became thicker.
6. Within species, strain energy U_m varied directly with wind strength.

     

Seed physiology: From ovule to maturing seed

1. The future of the seed is partly predetermined by events (flower formation, flowering, nutrient flow from mother plant, etc.) preceding fertilization and the formation of the gametophyte.
2. The environmental conditions under which the seed matures affect its final physiological constitution. This faet has mostly been neglected by seed physiologists.
3. It is not known how far the triantic nature of the diaspore (seed coat, pulp, etc., 2n of mother plant, embryon of δ +n of Φ, endosperm 2n of Φ +n of δ) affects seed development and germination.
4. The integuments of the ovules of some species have stomata. It is not known if they are functional in gas exchange or are constitutional non-functioning relics.
5. The causes of the growth-degeneration pattern of the nucellus are unknown.
6. During the development of the megaspore mother cell into the mature embryo sac dramatic cellular ultrastructural changes take place. This probably signifies a “change of guards” during which the gametophyte is freed from part of the controls by the ultrastructural units of the mother plant, preparing the ground after fertilization for a new, genetically independent sporophyte.
7. Upon closer examination, the seemingly simple processes of fertilization and embryogenesis, as described in textbooks, turn out to be very complex and full of problems. Is the role each male nucleus plays preordained or is it left to chance which male nucleus goes where? What causes the degeneration of the synergids and of the vegetative nucleus, and what protects the other two male nuclei from a similar fate? Which ultrastructural organelles are carried by the generative nuclei into their respective receptor cells and what is their role in them? Why do zygotes in some species develop after fertilization immediately into an embryo whereas in other species the zygote remains dormant for some time? What causes the polarity of the egg cell which, after fertilization, divides into one developmentally most active apical cell (giving rise to the embryo) and into another “lazy” basal cell which develops into the suspensor of “unknown function?”
8. In the source-sink relationship between photosynthesizing organs and the maturing seed there is one point at which the photosynthates pass from symplast to apoplast to symplast. The mechanism involved is largely unknown as well as the effect which environmental conditions have on this transport.

     

Chemolithotrophic growth and regulation of hydrogenase formation in the coryneform hydrogen bacterium strain 11/x

1. The present paper deals with the chemolithotrophic growth of a Gram-positive hydrogen bacterium strain 11/x which shows the characteristic features of some coryneform bacteria.
2. Like other hydrogen bacteria, the strain 11/x is a facultative chemolithotroph and grows on many organic substrates faster than in a mineral medium under an atmosphere of knallgas+CO₂. Fully induced, autotrophically grown cells, subcultured mixotrophically on fructose show additive growth.
3. Cell-free extracts of autotrophically grown cells are able to reduce methylene blue, dichlorophenolindophenol, phenazine methosulphate, menadione, and FMN with hydrogen. Conditions for direct NAD(P) reduction could not be found.
4. Hydrogenase is formed under autotrophic as well as mixotrophic conditions. In the latter case the rate of hydrogenase formation is diminished depending on the organic substrate. Heterotrophically grown cells do not have any detectable hydrogenase activity. For the induction of hydrogenase in those cells a nitrogen source is a prerequisite.
5. The formation of ribulose-1,5-diphosphate carboxylase and phosphoribulokinase seems to be regulated in a way similar to that of hydrogenase: the enzymes could only be detected in autotrophically and mixotrophically grown cells but not in those grown heterotrophically.

     

Amino acid receptor sites in the facial taste system of the sea catfish Arius felis

1. The amino acid sensitivity and specificity of the facial taste system of the marine catfish, Arius felis, is characterized electrophysiologically.
2. The facial taste system of Arius felis responded to all 28 amino acids tested, but was highly sensitive to only a few. In general, acidic amino acids and neutral amino acids with short side chains were more effective than imino, basic and neutral amino acids with long side chains.
3. A reciprocal cross-adaptation protocol used to characterize the receptor sites identified at least some relatively independent receptor sites for L-arginine, L-histidine, L-proline, L-alanine, glycine, D-alanine and L-glutamate.
4. Of the 7 amino acids that were indicated to have relatively independent receptor sites, the median electrophysiological threshold for L-alanine, the most stimulatory, and L-proline, the least stimulatory compounds, were 10 nM and 10,000 nM, respectively. The integrated facial taste response did not saturate at test amino acid concentrations up to 10 mM.
5. The generalized depression in responsiveness to test stimuli observed during amino acid adaptation is proposed to be a result of the co-distribution of sensitivity at the level of single taste cells rather than high cross-reactivity of the respective amino acid receptor sites for the test stimuli.

     

A study on the rate of water transport of the clam katelysia opima in relation to environmental conditions

1. The neutral red technique was employed to study the rate of filtration in Katelysia opima.
2. The weight specific water filtration was found to be greater for younger clams compared to the older ones.
3. The rate of water filtration increased with decreasing salinity.
4. Water filtration was found to increase as temperature increased, reaching a maximum at 35°C. but then sharply decreasing at 39°C.
5. Light had no significant effect on the rate of filtration.
6. Suspended matter was found to affect the rate of water filtration.
7. The rate of filtration was low at high pH and high in low pH.
8. The rate of water filtration was found to be faster during high tide than during low tide.
9. The presence of the parasitic crab, Pennotheris sp., in the mantle cavity of clams had a marked effect on the particle filtration.
10. Accidental cut of the siphon tips had no effect on the rate of filtration.

     

Charakterisierung eines phagenähnlichen Partikels aus Zellen von Nitrobacter

1. Polyhedral particles were isolated from cells of Nitrobacter winogradskyi and of Nitrobacter strains K₁, K₄ and α₁. Their physical and biological properties are characterized.
2. The investigated strains contain polyhedral particles, 1000–1200 Å in size. With increasing age of the culture more particles are found in cells of Nitrobacter. Simultaneously the number of colony producing nitritoxidants decreases.
3. In strain α₁ the loss of the capability to form colonies is connected with partial lysis of the cell and release of particles.
4. A homogeneous fraction of particles was obtained by zone density gradient centrifugation in Tris-Mg-SH-buffer.
5. The polyhedral particles have a sedimentation coefficient of s _w,20 ⁰ =825S and a CsCl-buoyant density of ?²⁵ g/cm³.
6. Based on the determined properties the particles are classified as phage-like Nitrobacter particles Nb₁.

     

Effects of Environmental Perturbations on Short-Term Phytoplankton Production off Lawson's Bay,A Tropical Coastal Embayment

1. The phytoplankton cycle off Lawson's Bay, Waltair follows a bimodal pattern with a major peak during March–May; a minor peak during October–November months and with a low production during the summer months i.e., June–August.
2. During the summer months of 1957, 1958, 1960 and 1962 dumping of dredged spoil from the entrance channel of the harbour into the sea resulted in a natural enrichment of waters.
3. Following this enrichment, there was a qualitative and quantitative increase in the phytoplankters thus leading to the development of a bloom.
4. Only Thalassiosira subtilis and Chaetoceros curvisetus commonly bloomed during the four years.
5. The increase in gross production which varied from 3–13 fold and the high photosynthesis-respiration ratios 5.1 to 10.5 indicated that the bloom populations were in a healthy state.
6. The decrease of the populations to the initial levels suggests that some unknown factor, other than those investigated must have been operating.
7. Consequences of eutrophication of different origins on stimulation of phytoplankton production are briefly discussed.

     

Das Vorkommen von Malatenzym und Malo-Lactat-Enzym bei verschiedenen Milchsäurebakterien

1. Malic enzyme was induced by malic acid and malo-lactic enzyme was induced by malic acid and glucose in cells of three strains ofLactobacillus casei that were able to grow on malate as carbon source. Two strains ofStreptococcus faecalis formed malic enzyme only, whereas only malo-lactic enzyme was formed by a glucose requiring strain ofStreptococcus lactis.
2. Given sequential induction, cells ofLactobacillus casei M40 were found to contain malic enzyme and malo-lactic enzyme simultaneously.
3. Malic enzyme and malo-lactic enzyme have been separated by chromatography on Sephadex G-200. These two enzymes have a different pH optimum, different affinities for substrates, form different end products from malate, and have molecular weights of 120000 and 150000 daltons respectively.

     

Die rezente Verbreitung der Flusskrebse in Hessen (Decapoda: Astacidae)

1. This investigation demonstrates the presence of three different species in Hessen (West Germany). By means of three maps the recent distribution is demonstrated.
2. Astacus astacus is still present in Hessen in small populations.
3. Austropotamobius torrentium is the rarest species and was recorded only in the Taunus-, Spessart- und Odenwald mountains.
4. Oronectes limosus, in the rivers Rhein and Main numerous before 1950, has become scarce. In the river Fulda there have been only two recordings in 1958.

     

Intracellular proteolytic activity in developing myxospores of Myxococcus xanthus

1. Cell-free extracts from vegetative cells and developing myxospores of Myxococcus xanthus were found to contain similar amounts of proteolytic activity, approximately 80% of which was due to one or more neutral metal proteases.
2. Sixty per cent of the proteolytic activity was particulate.
3. The specific activity of the proteases was high throughout all stages of myxospore formation and displayed small increases in activity at two stages of development: (1) during cell shortening and (2) immediately following the conversion to spheres. The first peak in activity was apparent in assays conducted at pH 8 or 10 whereas the second peak was obvious only at pH 6.
4. A mutant which develops into myxospores only after a lag of approximately 7–8 h possessed levels of proteases similar to the wild type and displayed a peak in proteolytic activity after a delay of 7–8 h.
5. Low levels of serine protease activity were occasionally detected in both vegetative cells and myxospores; no sulfhydryl proteases were detectable in either cell type.
6. Extracellular proteases accumulated in the medium throughout myxospore development but differed from the intracellular proteases in pH optima and sensitivity to inhibitors.

     

Growth of a floating aquatic weed,Salvinia under standard conditions

1. Growth of the floating aquatic weed, Salvinia, in sterile culture was exponential for at least 2 weeks under standardized conditions.
2. Increase in light intensity or in CO₂ resulted in increases in growth rate, but did not extend the exponential period of growth.
3. This aquatic plant, like many others, discriminates against calcium relative to strontium.
4. In culture Salvinia exhibited luxury consumption of N and P.
5. Because of high C/N ratios, Salvinia may not be a favorable source of animal food, but might be useful in nutrient removal schemes.
6. In sterile culture, S. molesta produced fewer leaves than S. minima, but maintained a significant increase in leaf area and dry weight. This may be correlated with the ability of the first species to rapidly spread over tropical waterways.

     

The anaerobic metabolism of malate of Saccharomyces bailii and the partial purification and characterization of malic enzyme

1. The main pathway of the anaerobic metabolism of l-malate in Saccharomyces bailii is catalyzed by a l-malic enzyme.
2. The enzyme was purified more than 300-fold. During the purification procedure fumarase and pyruvate decarboxylase were removed completely, and malate dehydrogenase and oxalacetate decarboxylase were removed to a very large extent.
3. Manganese ions are not required for the reaction of malic enzyme of Saccharomyces bailii, but the activity of the enzyme is increased by manganese.
4. The reaction of l-malic enzyme proceeds with the coenzymes NAD and (to a lesser extent) NADP.
5. The K _m-values of the malic enzyme of Saccharomyces bailii were 10 mM for l-malate and 0.1 mM for NAD.
6. A model based on the activity and substrate affinity of malic enzyme, the intracellular concentration of malate and phosphate, and its action on fumarase, is proposed to explain the complete anaerobic degradation of malate in Saccharomyces bailii as compared with the partial decomposition of malate in Saccharomyces cerevisiae.

     

Particularites de l'infestation adiaspiromycosique par Emmonsia crescens Emmons et Jellison, 1960 chez Pitymys subterraneus (De Selys-Longchamps 1836) et Mustela nivalis nivalis L. 1766

From the observation of some hundred lungs of small wild mammals in France, we have found two types of parasitism byEmmonsia crescens Emmons &Jellison, (1960). In most species, for example inApodemus sylvaticus andClethrionomys glareolus, the adiaspores ranged from 200 to 475 µ in diameter, their cell walls are 28 µ in average thickness and they cause a weak histological reaction in the parenchyma of the lungs. InPitymys subterraneus, the adiaspores are always much smaller, about 85 µ. They have a thin cell wall, 4 µ, and are surrounded by a strong histological reaction, the thickness of which ranges from 130 to 140 µ. The adiaspores observed inMustela nivalis nivalis are still smaller, about 70 µ, and they provoke a pulmonary reaction a hundred µ thick. However, we think that these small adiaspores belong to the speciesEmmonsia crescens Emmons &Jellison, (1960):

1. they germinate springing many mycelian tubes.
2. the macroscopic and microscopic morphological characteristics of the mycelian phase are identical to those of several strains ofEmmonsia crescens.
3. the mycelian phase completely turns into the yeast phase at 37° C on “Brain Heart Agar” Difco.
4. a strain isolated from aP. subterraneus, inoculated to a white mice, a bank vole or a field vole gives big adiaspores typical ofE. crescens in their respective lungs.
5. from an epidemiologic point of view, it is difficult to imagine such a narrow cohabitation of two species of so non specific germ having each its own host.

     

An ecological study of the Ponggol Estuary in Singapore

1. An ecological study of the Ponggol Estuary was conducted from July 1965 to June 1966 and the seasonal data on physical, chemical and biological characteristics were presented.
2. The Ponggol River represents a short, narrow and shallow estuary in Singapore. The river mouth is open throughout the year and water from eastern Johore Straits drains in twice a day at high tide. The upper reach, however, is left exposed at low tide.
3. The Ponggol River was classified as a vertically and laterally homogeneous estuary and was found to exhibit a mesohaline to polyhaline environment.
4. Significant hydrological gradients from the river mouth 10 the upper reach were noted in the river system. Salinity, dissolved oxygen and pH increased towards the mouth of the river and other parameters such as nutrients, dissolved organic matter and turbidity increased towards the source.
5. Although the river received organic pollutants at the upper reach the estuary was able to discharge them fairly rapidly through regular flushing by the tides. The transient rise of organic matter did not appear to impart any serious affect on the biota in the estuary.
6. Over 98% of the phytoplankton consisted of diatoms, most of which were brought into the estuary from eastern Johore Straits. Freshwater forms were relatively few.
7. Phytoplankton biomass was considerably higher than the adjoining waters. and was reduced at the upper reach due to high turbidity of the water.
8. 80% of the zooplankton was composed of dinoflagellates,Difflugia, copepods and bivalve larvae dominating at all sections of the estuary.
9. Percentage composition of the zooplankton showed that dinoflagellates and copepod nauplii predominated at high tide whileDifflugia and bivalve larvae were abundant at low tide.
10. Zooplankton standing crop, in general, was higher towards the source at high tide but the reverse was found at low tide, i.e. standing crop increased towards the river mouth. This was attributed to the process of concentration.
11. Species composition of zooplankton was found to be more or less similar to that of the eastern Johore Straits.
12. The nekton consisted predominantly of small and juvenile fish. Close correlation of fish and copepods was found to be statistically valid and it was concluded that the fish entered the estuary to feed rather than to spawn.
13. The squids formed an important catch of the beach seine unit and were caught throughout the year.
14. The fish population could be grouped into four categories: estuarine components, euryhaline components, marine components and migratory components.
15. Benthic invertebrates were abundant. Commercially important species consisted of prawns,Metapenaeus andPenaeus, and crabs,Neptunus pelagicus andScylla serrata.
16. The river bed was inhabited predominantly by molluscs and the distribution resembled that of the sheltered shore of muddy-sand type.

     

Metabolism of the anaerobic formation of succinic acid bySaccharomyces cerevisiae

1. Succinic acid is formed in amounts of 0.2–1.7 g/l by fermenting yeasts of the genusSaccharomyces during the exponential growth phase. No differences were observed between the various species, respiratory deficient mutants and wild type strains.
2. At low glucose concentrations the formation of succinic acid depended on the amount of sugar fermented. However, the nitrogen source was found to be of greater importance than the carbon source.
3. Of all nitrogen sources, glutamate yielded the highest amounts of succinic acid. Glutamate led to an oxidative and aspartate to a reductive formation of succinic acid.
4. A reductive formation of succinic acid by the citric acid cycle enzymes was observed with malate. This was partially inhibited by malonate. No evidence was obtained that the glyoxylate cycle is involved in succinic acid formation by yeasts.
5. Anaerobically grown cells ofSaccharomyces cerevisiae contained α-ketoglutarate dehydrogenase. Its activity was found in the 175000 x g sediment after fractionated centrifugation. The specific activity increased 6-fold after growth on glutamate as compared with cells grown on ammonium sulfate.
6. The specific activities of malate dehydrogenase, fumarase, succinate dehydrogenase, succinylcoenzymeA synthetase, α-ketoglutarate dehydrogenase and glutamate dehydrogenase (nicotinamide adenine dinucleotide dependent) were determined in yeast cells grown on glutamate or ammonium sulfate. Similar results were obtained with a wild type strain and a respiratory deficient mutant. The latter did not contain succinate dehydrogenase.
7. In fermenting yeasts succinic acid is mainly formed from glutamate by oxidation.

     

Protease and Amylase in the digestive tract ofBarbus paludinosus

1. Protease and amylase activity in the digestive system ofBarbus paludinosus Peters (Pisces, Cyprinidae) has been investigated.
2. Chromatographic analysis showed seven amino acids to be present in both the anterior and posterior intestine. Only leucine, phenylalanine, valine, glycine and aspartic acid were positively identified.
3. In the anterior intestine chromatography revealed two sugars, but only one in the posterior intestine which was identified as glucose.
4. The pH of the intestinal fluid was found to be 5.8 and 7.8 for the fore and hind gut respectively, This correlates well with the enzyme pH optima found in in vitro experiments.
5. Protease and amylase activity was found throughout the digestive tract. Maximum proteolytic activity being present in the anterior intestine. Amylase activity is similar in both regions of the gut.
6. Correlation between the digestive enzymes and the fishes diet is briefly discussed.

     

Field studies on the variability of populations of Aster tripolium L. in relation to saltmarsh zonation

1. Aster tripolium is a very variable species of which a number of types have been described both on a morphological and ecological level.
2. In permanent plots along the height gradient in the salt marsh it appeared that differences in the A. tripolium subpopulations occur.
3. In the lowest zone of the marsh, dominated by Spartina anglica (Spartinion), the mean life expectancy of individual adult plants is relatively high but it is relatively low for seedlings.
4. In the higher zones of the marsh the mean life expectancy is relatively lower, but for the seedlings it is higher (Puccinellion maritimae).
5. In the Spartina-zone individual A. tripolium plants have about twice the number of shoots as the plants from the other zones.
6. The plants from the Spartina zone produce per individual more generative shoots (absolute) but these have less capitula than elsewhere in the marsh. The number of ripe seeds per head is almost constant everywhere in the marsh.

     

Growth of Nitrobacter in the presence of organic matter

1. Culture filtrates of heterotrophic bacteria were tested for their stimulatory effect on nitrification of three strains of Nitrobacter.
2. Yeast extract-peptone solution, in which Pseudomonas fluorescens had grown, after removal of the cells was added to autotrophically growing cultures of Nitrobacter agilis; it caused a stimulated nitrite oxidation and growth of Nitrobacter agilis.
3. The degree of stimulation depended on: a) the proportion of the culture filtrate to the autotrophic medium; b) the composition of the complex medium in which Pseudomonas fluorescens had been grown; c) the time the heterotrophic bacterium had been grown in the complex medium.
4. The stimulatory effect was highest with Nitrobacter agilis, less with Nitrobacter winogradskyi and negligible with Nitrobacter K ₄.
5. It was possible to adapt nitrifying cells of Nitrobacter agilis to higher concentrations of yeast extract and peptone. After the nitrite had been completely oxidized the cell-N still increased up to 30% before growth stopped.

     

In vivo buccal nerve activity that distinguishes ingestion from rejection can be used to predict behavioral transitions in Aplysia

1. We are studying the neural basis of consummatory feeding behavior in Aplysia using intact, freely moving animals.
2. Video records show that the timing of radula closure during the radula protraction-retraction cycle constitutes a major difference between ingestion (biting or swallowing) and rejection. During ingestion, the radula is closed as it retracts. During rejection, the radula is closed as it protracts.
3. We observed two patterns of activity in nerves which are likely to mediate these radula movements. Patterns I and II are associated with ingestion and rejection, respectively, and are distinguished by the timing of radula nerve activity with respect to the onset of buccal nerve 2 activity.
4. The association of ingestion with pattern I is maintained when the animal feeds on a polyethylene tube, the same food substrate used to elicit rejection responses. Under these conditions, pattern I is associated with either swallowing or no net tube movement.
5. Most transitions from swallowing to rejection were preceded by one or more occurrences of pattern I in which there was no net tube movement, suggesting that these transitions can be predicted.
6. Our data suggest that these two patterns can be used to distinguish ingestion from rejection.