scholarly journals The synthesis of acetylcholine by plants

1981 ◽  
Vol 194 (1) ◽  
pp. 361-364 ◽  
Author(s):  
B N Smallman ◽  
A Maneckjee

Choline acetyltransferase was demonstrated in nettles (Urtica dioica), peas (Pisum sativum), spinach (Spinacia oleracea), sunflower (Helianthus annuus) and blue–green algae by using a Sepharose–CoASH affinity column. The column effected a 1500-fold purification of the enzyme from nettle homogenates and was required for demonstrating activity in the other higher plants. Demonstration of the enzyme in blue-green algae suggests that acetylcholine was a biochemical necessity in the earliest photosynthetic organisms.

2014 ◽  
Vol 1065-1069 ◽  
pp. 114-118
Author(s):  
Shuo Fu Tian ◽  
Chao Jin Lu ◽  
Yuan Wang

It is the components, living things evolution processes, development environments, distribution layers and the earliest time for coal series formation that are investigated and studied in detail based on the author’s graduation thesis, the “Geobiology” , the “China coal petrology” and the other’s some references in this paper. And it is considered that mainly two types of the Coal Series might be distinguish in the geologic history in China, respectively consisted of the lower organisms (especially the lower plants, blue-green algae) and higher organisms (especially the higher plants, pteridophyta, gymnosperms, Anthophyta). Meanwhile, the conclusions can be drawn that the development of the organisms is not only controlled by the environments, on the other hand, the environments and their sediments are also affected by the ecologies of the organisms. So the coal bed or coal series can be used as the marks of the environment explanation, perhaps having some Significances of Geobiology. In additional, the relationship with an unconformity or disconformity is discussed here, too.


1959 ◽  
Vol 10 (3) ◽  
pp. 322 ◽  
Author(s):  
EJF Wood

There are four plant communities in Lake Macquarie: the see-grass community, the reef community, the mud bottom community, and the phytoplankton community. Biologically, the sea-grass community is regarded as being the most important. The epiphytes on the sea-grasses are largely used as food by phytophagous fish and other animals. The reef community consists of larger brown algae which are not of themselves of great importance, and of felts of blue-green algae such as Ectocarpus, and other filamentous forms which are important. Photosynthetic organisms are sparse in the mud bottoms, except for the tapetic organisms in the sea. Phytoplankton is relatively abundant.


1970 ◽  
Vol 117 (3) ◽  
pp. 593-600 ◽  
Author(s):  
G. R. Whistance ◽  
D. R. Threlfall

1. By means of 14C tracer experiments and isotope competition experiments the roles of d-tyrosine, p-hydroxyphenylpyruvic acid, p-hydroxyphenylacetic acid, phenylacetic acid, homogentisic acid and homoarbutin (2-methylquinol 4-β-d-glucoside) in the biosynthesis of plastoquinones, tocopherols and α-tocopherolquinone by maize shoots was investigated. It was established that d-tyrosine, p-hydroxyphenylpyruvic acid and homogentisic acid can all be utilized for this purpose, whereas p-hydroxyphenylacetic acid, phenylacetic acid and homoarbutin cannot. Studies on the mode of incorporation of d-tyrosine, p-hydroxyphenylpyruvic acid and homogentisic acid showed that their nuclear carbon atoms and the side-chain carbon atom adjacent to the nucleus give rise (as a C6-C1 unit) to the p-benzoquinone rings and nuclear methyl groups (one in each case) of plastoquinone-9 and α-tocopherolquinone and the aromatic nuclei and nuclear methyl groups (one in each case) of γ-tocopherol and α-tocopherol. 2. By using [14C]-homogentisic acid it has been shown that homogentisic acid is also a precursor of plastoquinone, tocopherols and α-tocopherolquinone in the higher plants Lactuca sativa and Rumex sanguineus, the green algae Chlorella pyrenoidosa and Euglena gracilis and the blue–green alga Anacystis nidulans.


1977 ◽  
Vol 168 (2) ◽  
pp. 205-209 ◽  
Author(s):  
R Cammack ◽  
K K Rao ◽  
C P Bargeron ◽  
K G Hutson ◽  
P W Andrew ◽  
...  

Midpoint potentials of plant-type ferredoxins from a range of sources were measured by redox titrations combined with electron-paramagnetic-resonance spectroscopy. For ferredoxins from higher plants, green algae and most red algae, the midpoint potentials (at pH 8.0) were between —390 and —425 mV. Values for the major ferredoxin fractions from blue-green algae were less negative (between —325 and —390 mV). In addition, Spirulina maxima and Nostoc strain MAC contain second minor ferredoxin components with a different potential, —305 mV (the highest so far measured for a plant-algal ferrodoxin) for Spirulina ferrodoxin II, and —455 mV (the lowest so far measured for a plant-algal ferredoxin) for Nostoc strain MAC ferredoxin II. However, two ferredoxins extracted from a variety of the higher plant Pisum sativum (pea) had midpoint potentials that were only slightly different from each other. These values are discussed in terms of possible roles for the ferredoxins in addition to their involvement in photosynthetic electron transport.


1970 ◽  
Vol 15 ◽  
pp. 23-34
Author(s):  
MZ Islam ◽  
S Begum ◽  
H Ara ◽  
TM Waliullah

The study was carried out to determine the effects of pesticide on the growth and nitrogen fixation by blue green algae (BGA) that isolated from three different soils of Bangladesh viz., saline soil, calcareous soil and red soil. Furadan 5G, one of the most commonly used pesticides was selected for the study of eighteen taxa of blue green algae (BGA) which brought under the unialgal culture in the selected soil types. Variations observed in growth and nitrogen fixation among the isolates of a particular type of soil. The culture resulted as BGA grow slow under heterotrophically grown cultures than that of autotrophically grown cultures. On the other hand, nitrogen fixation in heterotrophically grown cultures was observed at higher rate. However satisfactory result was observed in both cases when field dose of Furadan was applied practically. In this case, heterotrophically grown cultures were more tolerant to pesticides with respect to growth and nitrogen fixation. Key words: Blue green algae, Furadan, nitrogen fixation, heterotrophic growth, autotrophic growth.   doi: 10.3329/jbs.v15i0.2199 J. bio-sci. 15: 23-34, 2007


1954 ◽  
Vol 2 (2) ◽  
pp. 154 ◽  
Author(s):  
AB Wardrop

Crossed lamellar structures in cell walls have been known to occur with certainty only in some green algae. A number of higher plants in which it was considered this structure might be present have been examined, and it has been demonstrated in the phloem fibres of Vinca major and the tracheidal elements of the aerial root of Alstonia spathulata. In the latter two types of crossed structure are recognized, in one bands of laterally associated microfibrils c. 0.5µ wide intersect at variable angles, whereas in the other lateral association is complete, forming a crossed lamellar structure which approaches most nearly that occurring in the algae. In the outer layer of the secondary wall of wood fibres of Eucalyptus elaeophora and E. regnans there is inconclusive evidence of a crossed structure similar to that observed in the cell walls of some vessels, which consists of a loosely formed meshwork of aggregates of microfibrils. This structure is considered to be distinct from the crossed lamellar and cross-banded structures.


1977 ◽  
Vol 32 (1-2) ◽  
pp. 118-124 ◽  
Author(s):  
Georg H. Schmid ◽  
Helga List ◽  
Alfons Radunz

An antiserum to lutein agglutinates thylakoids of Nostoc muscorum and Oscillatoria chalybea. From this it follows that lutein is located in the outer surface of the thylakoid membrane of these blue-green algae. The same result is obtained for an antiserum to neoxanthin. As neoxanthin is supposed not to occur in blue-green algae it follows that in this case the antibody action should be directed towards a carotenoid with allenic structure. The antisera to lutein and neoxanthin inhibit in both investigated algal species photosynthetic electron transport on the oxygen-evolving side of photosystem II. Moreover, the inhibition sites of both antisera are identical in Nostoc muscorum and are located between the sites of electron donation of the artificial electron donors tetramethyl benzidene and diphenylcarbazide. In the case of the blue-green alga Oscillatoria chalybea the inhibition sites of both antisera differ. Whereas the inhibition site of the antiserum to neoxanthin lies again between the sites of electron donation of tetramethyl benzidine and di­phenylcarbazide, the inhibition site of the antiserum to lutein appears to be situated at least partially beyond the site of electron donation of tetramethyl benzidine. The degree of inhibition of electron transport reactions with Nostoc muscorum is for both antisera 50 - 60 per cent and is pH-dependent. The pH-optimum lies at pH 7.2 for the antiserum to neoxanthin and at 7.8 for the antiserum to lutein. In comparison to this data the same antisera inhibit electron transport in chloroplasts from higher plants only by 20%. This low degree of inhibition in higher plants is apparently due to the fact that the surfaces of the thylakoids are not accessible to antibodies within the grana. In contrast to this the thylakoid surfaces of blue-green algae are fully accessible because the thylakoids are unstacked. The thylakoids of Oscillatoria chalybea have the tendency towards aggregation. Therefore, the results concerning the accessibility of the carotenoids to antibodies are not so clear cut as with Nostoc muscorum.


1961 ◽  
Vol 9 (1) ◽  
pp. 63-80 ◽  
Author(s):  
Hans Ris ◽  
R. N. Singh

Several species of blue-green algae were studied in thin sections with the electron microscope. Our electron micrographs confirm the view that the cell of blue-green algae is different and simpler in organization than the typical plant or animal cell. On the other hand, the general pattern of ultrastructure is the same as that found in bacteria and Streptomyces. The cell boundary is formed by a double membrane which consists of two typical unit membranes. Situated in between these membranes is the dense inner investment or wall which continues uninterrupted into the cross-walls. The cells always contain photosynthetic lamellae, nucleoplasm with DNA, small granules resembling ribosomes, and often also a number of larger granules of various sorts. The photosynthetic membranes either form the boundary of vesicles or flattened sacs, or, when the lumen of the vesicles disappears and the vesicular surfaces of the membranes zip together, they appear as lamellae made of two closely applied unit membranes. These vesicles or lamellae are disposed irregularly through the cell or arranged in parallel stacks of two or more. A thin layer of cytoplasm always separates the lamellae. The nucleoplasm is composed of masses of fine fibrils about 25 A thick and is either dispersed through the cell or concentrated in polymorphous reticular structures near the center of the cell. The improved resolution of the electron microscope makes it obvious that the terms "chromatoplasm" and "centroplasm" commonly used in the description of blue-green algae are really misleading. There are not different kinds of cytoplasm, but the cell consists of various structural (and functional) units like the ones mentioned above, which are arranged in the cell in a number of ways characteristic for each species or for different physiological or developmental states.


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