Physiology and biochemistry of autotrophic bacteria

1987 ◽  
Vol 53 (1) ◽  
pp. 3-14 ◽  
Author(s):  
G. A. Codd ◽  
J. G. Kuenen
Keyword(s):  
Autotrophic Bacteria ◽  
Physiology And Biochemistry

Some Effects of Oxidant Air Pollutants (Ozone and Peroxyacetyl Nitrate) on the Ultrastructure of Leaf Tissues

1972 ◽  
Vol 30 ◽  
pp. 360-361
Author(s):  
William W. Thomson ◽  
Elizabeth S. Swanson
Keyword(s):  
Air Pollutants ◽  
Electron Microscopic Examination ◽  
Peroxyacetyl Nitrate ◽  
Electron Microscopic ◽  
Growth Physiology ◽  
Physiology And Biochemistry ◽  
Entire Plant ◽  
Leaf Tissues ◽  
Gaseous Hydrocarbons ◽  
The Individual

The oxidant air pollutants, ozone and peroxyacetyl nitrate, are produced in the atmosphere through the interaction of light with nitrogen oxides and gaseous hydrocarbons. These oxidants are phytotoxicants and are known to deleteriously affect plant growth, physiology, and biochemistry. In many instances they induce changes which lead to the death of cells, tissues, organs, and frequently the entire plant. The most obvious damage and biochemical changes are generally observed with leaves.Electron microscopic examination of leaves from bean (Phaseolus vulgaris L.) tobacco (Nicotiana tabacum L.) and cotton (Gossipyum hirsutum L.) fumigated for .5 to 2 hours with 0.3 -1 ppm of the individual oxidants revealed that changes in the ultrastructure of the cells occurred in a sequential fashion with time following the fumigation period. Although occasional cells showed severe damage immediately after fumigation, the most obvious change was an enhanced clarity of the cell membranes.

Organizing a public aquarium: objectives, design, operation and missions. A review

2013 ◽  
Vol 13 (4) ◽  
pp. 369-384
Keyword(s):  
Life Cycles ◽  
Ex Situ ◽  
Responsible Behavior ◽  
Scientific Disciplines ◽  
Public Aquarium ◽  
Physiology And Biochemistry ◽  
Taxonomic Concept ◽  
Conservation Projects ◽  
Surrounding Areas ◽  
Community Concept

Many Public Aquaria have been designed and constructed all over the world during the last three decades. The serial arrangement of relatively small, rectangular, concrete tanks has been replaced by fewer large, irregularly shaped tanks, replicating habitats. The “taxonomic concept” of displaying specimens in the old aquaria has now been succeeded by the more ecological, “community concept” type of display. At the same time most of the “old aquaria” have been renovated. Aquarium missions have also been broadened nowadays including research, conservation and education. Aquaria are ideal places for research on husbandry, life cycles, reproduction, behavior, autoecology and fish pathology. Collaboration with Universities and Research Centers increases the research potential in scientific disciplines such as ecology, genetics, physiology and biochemistry. Collaboration also provides mutual benefits in both infrastructure and personnel: The research background in aquaria also forms a sound platform to materialize conservation projects, focusing either on the ex-situ conservation of animals in the aquaria or on environmental protection of surrounding areas and reintroduction of endangered species. In addition to formal educational opportunities, non formal education to visitors, schools and undergraduates seems to become a major mission of aquaria. Aquarium tank displays, preserved biological material, film projections, seminars / lectures and book magazine publications enhance environmental awareness, encouraging people to adopt Environmentally Responsible Behavior. All these missions are feasible because most public aquaria are making a good profit mainly due to their high popularity. There are also benefits for the community in the area; aquaria have enlivened declining water front areas and increased the income of tourist resorts mainly by “stretching out” the tourist season. In the present work the objectives of a public aquarium are reviewed and the main infrastructure subsystems and operational procedures are described; Know how on aquarium systems can also be applied in research laboratories of academic institutions if live organisms have to be kept for experimentation. Aquarium missions on research, conservation and education are discussed.

scholarly journals Biochar Mediated-Alleviation of Chromium Stress and Growth Improvement of Different Maize Cultivars in Tannery Polluted Soils

2021 ◽  
Vol 18 (9) ◽  
pp. 4461
Author(s):  
Muhammad Asaad Bashir ◽  
Xiukang Wang ◽  
Muhammad Naveed ◽  
Adnan Mustafa ◽  
Sobia Ashraf ◽  
...  
Keyword(s):  
Soluble Sugars ◽  
Cultivar Differences ◽  
Leather Industry ◽  
Polluted Soils ◽  
Chlorophyll Pigments ◽  
Growth Physiology ◽  
Maize Cultivars ◽  
Physiology And Biochemistry ◽  
Cr Toxicity ◽  
Relative Water

Soil pollution with heavy metal is a serious problem across the globe and is on the rise due to the current intensification of chemical industry. The leather industry is one of them, discharging chromium (Cr) in huge quantities during the process of leather tanning and polluting the nearby land and water resources, resulting in deterioration of plant growth. In this study, the effects of biochar application at the rate of 3% were studied on four maize cultivars, namely NK-8441, P-1543, NK-8711, and FH-985, grown in two different tannery polluted Kasur (K) and Sialkot (S) soils. Maize plants were harvested at vegetative growth and results showed that Cr toxicity adversely not only affected their growth, physiology, and biochemistry, but also accumulated in their tissues. However, the level of Cr toxicity, accumulation, and its influence on maize cultivars varied greatly in both soils. In this pot experiment, biochar application played a crucial role in lessening the Cr toxicity level, resulting in significant increase in plant height, biomass (fresh and dry), leaf area, chlorophyll pigments, photosynthesis, and relative water content (RWC) over treatment set as a control. However, applied biochar significantly decreased the electrolyte leakage (EL), antioxidant enzymes, lipid peroxidation, proline content, soluble sugars, and available fraction of Cr in soil as well as Cr (VI and III) concentration in root and shoot tissues of maize plant. In addition to this, maize cultivar differences were also found in relation to their tolerance to Cr toxicity and cultivar P-1543 performed better over other cultivars in both soils. In conclusion, biochar application in tannery polluted soils could be an efficient ecofriendly approach to reduce the Cr toxicity and to promote plant health and growth.

scholarly journals THE PRESENCE OF AN ENDOGENOUS RESPIRATION IN THE AUTOTROPHIC BACTERIA

1942 ◽  
Vol 25 (4) ◽  
pp. 617-622 ◽  
Author(s):  
K. G. Vogler
Keyword(s):  
Oxygen Uptake ◽  
Organic Materials ◽  
Endogenous Respiration ◽  
Thiobacillus Thiooxidans ◽  
Autotrophic Bacteria ◽  
Autotrophic Bacterium

It is shown that there exists in the autotrophic bacterium Thiobacillus thiooxidans a measurable oxygen uptake in the absence of the specific nutrient (sulfur). This respiration is shown to be due to the utilization of organic materials which must have been previously synthesized by the chemosynthetic process, providing evidence that autotrophic bacteria contain a dissimilatory process which involves the breakdown of organic materials and furnishes energy for the maintenance of the cell during periods in which the specific nutrient is absent. This is entirely in accord with the work of Bömeke (1939), who provided similar types of proof for Nitrosomonas and Nitrobacter. One may conclude, therefore, that autotrophic bacteria possess an endogenous respiration which involves the utilization of previously synthesized organic materials.

Sign in / Sign up

Export Citation Format

Share Document