The Lipoxygenase of Reticulocytes. Purification, Characterization and Biological Dynamics of the Lipoxygenase; Its Identity with the Respiratory Inhibitors of the Reticulocyte

Utilizing monolayers of human polymorphonuclear leukocytes, optimal conditions for attachment and ingestion of Neisseria gonorrhoeae were determined. Both attachment and ingestion were optimal at 36 degrees C when a bacteria-leukocyte ratio of 100:1 was employed. After 30 min of incubation, log-phase viable type 2 gonococci were attached to 90% of leukocytes, whereas log-phase viable type 4 gonococci were ingested by 80 to 90% of cells. Respiratory inhibitors had no effect on attachment or ingestion, whereas glycolytic inhibitors blocked ingestion but did not affect attachment of gonocci to the leukocyte surface. Inhibition was dose dependent and partially reversible. The oxidative metabolism of leukocytes with gonococci attached or ingested was also examined. Attachment of log-phase type 2 gonococci stimulated a minimal increase in glucose oxidation and oxygen consumption by leukocytes in contrast to marked increases by leukocytes that had ingested viable type 4 or heat-killed typed 2 organisms. These results demonstrate that attachment of log-phase type 2 gonococci to the surface membrane does not stimulate significant leukocyte oxidative metabolism nor initiate the phagocytic process.

Download Full-text

ATP compartmentation in plastids and cytosol ofArabidopsis thalianarevealed by fluorescent protein sensing

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1711497115 ◽

2018 ◽

Vol 115 (45) ◽

pp. E10778-E10787 ◽

Cited By ~ 16

Author(s):

Chia Pao Voon ◽

Xiaoqian Guan ◽

Yuzhe Sun ◽

Abira Sahu ◽

May Ngor Chan ◽

...

Keyword(s):

Arabidopsis Thaliana ◽

Fluorescent Protein ◽

Higher Plants ◽

Electron Flow ◽

Cyclic Electron Flow ◽

Linear Electron ◽

Protein Sensing ◽

Atp Production ◽

Respiratory Inhibitors ◽

Sensor Protein

Matching ATP:NADPH provision and consumption in the chloroplast is a prerequisite for efficient photosynthesis. In terms of ATP:NADPH ratio, the amount of ATP generated from the linear electron flow does not meet the demand of the Calvin–Benson–Bassham (CBB) cycle. Several different mechanisms to increase ATP availability have evolved, including cyclic electron flow in higher plants and the direct import of mitochondrial-derived ATP in diatoms. By imaging a fluorescent ATP sensor protein expressed in livingArabidopsis thalianaseedlings, we found that MgATP2−concentrations were lower in the stroma of mature chloroplasts than in the cytosol, and exogenous ATP was able to enter chloroplasts isolated from 4- and 5-day-old seedlings, but not chloroplasts isolated from 10- or 20-day-old photosynthetic tissues. This observation is in line with the previous finding that the expression of chloroplast nucleotide transporters (NTTs) inArabidopsismesophyll is limited to very young seedlings. Employing a combination of photosynthetic and respiratory inhibitors with compartment-specific imaging of ATP, we corroborate the dependency of stromal ATP production on mitochondrial dissipation of photosynthetic reductant. Our data suggest that, during illumination, the provision and consumption of ATP:NADPH in chloroplasts can be balanced by exporting excess reductants rather than importing ATP from the cytosol.

Download Full-text

Reversion from Light-Induced Inhibition of Seed Germination by Respiratory Inhibitors

PLANT PHYSIOLOGY ◽

10.1104/pp.74.1.186 ◽

1984 ◽

Vol 74 (1) ◽

pp. 186-188

Author(s):

Noriaki Tanno

Keyword(s):

Seed Germination ◽

Respiratory Inhibitors

Download Full-text

Biokinesis: A Soft Kinetic Architectural Skin

Leonardo ◽

10.1162/leon_a_01352 ◽

2017 ◽

Vol 50 (1) ◽

pp. 76-76

Author(s):

Jae Wan Park ◽

Ju Yeon Kim

Keyword(s):

Genetic Algorithm ◽

Morphological Transformations ◽

Biological Dynamics

This article proposes a soft kinetic architectural skin that represents natural, formative intelligence. Biokinesis is an interactive kinetic installation that performs soft, dynamic movements through morphological transformations based on a genetic algorithm. In this article, the authors present new possibilities for the kinetic skin by interpreting mechanical movements as holistic, biological dynamics.

Download Full-text

Coralivoría del gasterópodo Jenneria pustulata (Ovulidae: Pediculariinae) en dos arrecifes coralinos del PNN isla Gorgona

Bulletin of Marine and Coastal Research ◽

10.25268/bimc.invemar.2018.47.2.744 ◽

2018 ◽

Vol 47 (2) ◽

Author(s):

Mauro Giovanni Zucconi ◽

Levy D. Obonaga ◽

Edgardo Londoño-Cruz

Keyword(s):

Coral Reefs ◽

Coral Species ◽

Size Structure ◽

Coral Tissue ◽

Laboratory Conditions ◽

Set Up ◽

Biological Dynamics ◽

Colombian Pacific

Coral reefs are very important and highly biodiverse ecosystems that are exposed to various stressors, including biological ones, such as parasitism and corallivory – the direct consumption of coral tissue by a predator. Knowledge on the effects of corallivory on the coral reefs in the Colombian Pacific is poor. Therefore a study was set up to quantify the abundance of and the corallivory rate by the snail Jenneria pustulata in La Azufrada and Playa Blanca coral reefs (Gorgona Island, Colombia). Snails were manually sampled from the underside of Pocillopora sp. colonies and measured in situ to determine their size structure for each reef. To measure possible damage caused by corallivory, several snails were kept under controlled laboratory conditions for 24 h. Snail sizes and corallivory varied significantly between reefs (P=0.0001; P«0.001). Snails from Playa Blanca were larger than snails from La Azufrada, while corallivory was higher in La Azufrada than in Playa Blanca. Although corallivory rates by J. pustulata are smaller than rates reported for other predators in different coral species, it is recommended to continue this kind of investigations in order to increase the knowledge on biological dynamics of this species and to understand how they affect the reefs at Gorgona Island.

Download Full-text