The globin superfamily: functions in nitric oxide formation and decay

Abstract Globin proteins are ubiquitous in living organisms and carry out a variety of functions related to the ability of their prosthetic heme group to bind gaseous ligands, such as oxygen, nitric oxide (NO), and CO. Moreover, they catalyze important reactions with nitrogen oxide species, such as NO dioxygenation and nitrite reduction. The formation of NO from nitrite is a reaction catalyzed by globins that has received increasing attention due to its potential as a hypoxic NO signaling mechanism. In this review, we revisit the current knowledge about the role of globins in NO formation and its physiological implications.

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Recent insights into nitrite signaling processes in blood

Biological Chemistry ◽

10.1515/hsz-2016-0263 ◽

2017 ◽

Vol 398 (3) ◽

pp. 319-329 ◽

Cited By ~ 9

Author(s):

Christine C. Helms ◽

Xiaohua Liu ◽

Daniel B. Kim-Shapiro

Keyword(s):

Nitric Oxide ◽

Human Physiology ◽

Blood Cell ◽

Red Blood Cell ◽

Nitrite Reduction ◽

No Production ◽

The Past ◽

Acidic Conditions ◽

Hypoxic Vasodilation

Abstract Nitrite was once thought to be inert in human physiology. However, research over the past few decades has established a link between nitrite and the production of nitric oxide (NO) that is potentiated under hypoxic and acidic conditions. Under this new role nitrite acts as a storage pool for bioavailable NO. The NO so produced is likely to play important roles in decreasing platelet activation, contributing to hypoxic vasodilation and minimizing blood-cell adhesion to endothelial cells. Researchers have proposed multiple mechanisms for nitrite reduction in the blood. However, NO production in blood must somehow overcome rapid scavenging by hemoglobin in order to be effective. Here we review the role of red blood cell hemoglobin in the reduction of nitrite and present recent research into mechanisms that may allow nitric oxide and other reactive nitrogen signaling species to escape the red blood cell.

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New insights into the activity of Pseudomonas aeruginosa cd1 nitrite reductase

Biochemical Society Transactions ◽

10.1042/bst0361155 ◽

2008 ◽

Vol 36 (6) ◽

pp. 1155-1159 ◽

Cited By ~ 14

Author(s):

Serena Rinaldo ◽

Alessandro Arcovito ◽

Giorgio Giardina ◽

Nicoletta Castiglione ◽

Maurizio Brunori ◽

...

Keyword(s):

Nitric Oxide ◽

Pseudomonas Aeruginosa ◽

Nitrite Reductase ◽

Nitrite Reduction ◽

Nitrite Reductases ◽

Cytochrome Cd1 ◽

Haem Iron ◽

Shed Light ◽

Denitrification Process

The cytochrome cd1 nitrite reductases are enzymes that catalyse the reduction of nitrite to nitric oxide (NO) in the bacterial energy conversion denitrification process. These enzymes contain two different redox centres: one covalently bound c-haem, which is reduced by external donors, and one peculiar d1-haem, where catalysis occurs. In the present paper, we summarize the current understanding of the reaction of nitrite reduction in the light of the most recent results on the enzyme from Pseudomonas aeruginosa and discuss the differences between enzymes from different organisms. We have evidence that release of NO from the ferrous d1-haem occurs rapidly enough to be fully compatible with the turnover, in contrast with previous hypotheses, and that the substrate nitrite is able to displace NO from the d1-haem iron. These results shed light on the mechanistic details of the activity of cd1 nitrite reductases and on the biological role of the d1-haem, whose presence in this class of enzymes has to date been unexplained.

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Signalling functions of coenzyme A and its derivatives in mammalian cells

Biochemical Society Transactions ◽

10.1042/bst20140146 ◽

2014 ◽

Vol 42 (4) ◽

pp. 1056-1062 ◽

Cited By ~ 18

Author(s):

Hongorzul Davaapil ◽

Yugo Tsuchiya ◽

Ivan Gout

Keyword(s):

Mammalian Cells ◽

Coenzyme A ◽

Current Knowledge ◽

Pantothenic Acid ◽

Future Developments ◽

Malonyl Coa ◽

Vitamin B5 ◽

Coa Thioesters ◽

Living Organisms

In all living organisms, CoA (coenzyme A) is synthesized in a highly conserved process that requires pantothenic acid (vitamin B5), cysteine and ATP. CoA is uniquely designed to function as an acyl group carrier and a carbonyl-activating group in diverse biochemical reactions. The role of CoA and its thioester derivatives, including acetyl-CoA, malonyl-CoA and HMG-CoA (3-hydroxy-3-methylglutaryl-CoA), in the regulation of cellular metabolism has been extensively studied and documented. The main purpose of the present review is to summarize current knowledge on extracellular and intracellular signalling functions of CoA/CoA thioesters and to speculate on future developments in this area of research.

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Fungal Production and Manipulation of Plant Hormones

Current Medicinal Chemistry ◽

10.2174/0929867324666170314150827 ◽

2018 ◽

Vol 25 (2) ◽

pp. 253-267 ◽

Cited By ~ 8

Author(s):

Sandra Fonseca ◽

Dhanya Radhakrishnan ◽

Kalika Prasad ◽

Andrea Chini

Keyword(s):

Stress Responses ◽

Current Knowledge ◽

Critical Role ◽

Plant Defence ◽

Pathogenic Fungi ◽

Plant Responses ◽

Defensive Strategies ◽

Hormone Balance ◽

Living Organisms

Living organisms are part of a highly interconnected web of interactions, characterised by species nurturing, competing, parasitizing and preying on one another. Plants have evolved cooperative as well as defensive strategies to interact with neighbour organisms. Among these, the plant-fungus associations are very diverse, ranging from pathogenic to mutualistic. Our current knowledge of plant-fungus interactions suggests a sophisticated coevolution to ensure dynamic plant responses to evolving fungal mutualistic/pathogenic strategies. The plant-fungus communication relies on a rich chemical language. To manipulate the plant defence mechanisms, fungi produce and secrete several classes of biomolecules, whose modeof- action is largely unknown. Upon perception of the fungi, plants produce phytohormones and a battery of secondary metabolites that serve as defence mechanism against invaders or to promote mutualistic associations. These mutualistic chemical signals can be co-opted by pathogenic fungi for their own benefit. Among the plant molecules regulating plant-fungus interaction, phytohormones play a critical role since they modulate various aspects of plant development, defences and stress responses. Intriguingly, fungi can also produce phytohormones, although the actual role of fungalproduced phytohormones in plant-fungus interactions is poorly understood. Here, we discuss the recent advances in fungal production of phytohormone, their putative role as endogenous fungal signals and how fungi manipulate plant hormone balance to their benefits.

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Nitric oxide formation from nitroglycerin: role of cysteine

The Japanese Journal of Pharmacology ◽

10.1016/s0021-5198(19)46691-2 ◽

1995 ◽

Vol 67 ◽

pp. 182

Author(s):

Yoko Aniva ◽

Naoko Uehara ◽

Toshihiro Matsuzaki ◽

Matao Sakanashi

Keyword(s):

Nitric Oxide ◽

Oxide Formation ◽

Nitric Oxide Formation

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Ammonium transport: unifying concepts and unique aspects

Functional Plant Biology ◽

10.1071/pp01070 ◽

2001 ◽

Vol 28 (9) ◽

pp. 959 ◽

Cited By ~ 1

Author(s):

Anne van Dommelen ◽

René de Mot ◽

Jos Vanderleyden

Keyword(s):

Current Knowledge ◽

Natural Habitat ◽

Physiological Role ◽

Ammonium Uptake ◽

Ammonium Transport ◽

Symbiotic Interaction ◽

Ammonium Transporters ◽

Operating Current ◽

Living Organisms

This paper originates from an address at the 8th International Symposium on Nitrogen Fixation with Non-Legumes, Sydney, NSW, December 2000 Ammonium uptake by cells has been studied for more than a century, but only recently a family of ammonium transporters (Mep/Amt) with 10–12 transmembrane domains has been defined. These proteins are probably ubiquitous, since homologues have been found in the major kingdoms of living organisms. Plants as well as yeast and some archaebacteria have multiple Mep/Amt paralogues, which can be distinguished by their affinity for ammonium and the ammonium analogue methylammonium. Most ammonium transporters are induced in nitrogen-starving conditions, both in prokaryotes and plants. In Saccharomyces cerevisiae, Escherichia coli and Azospirillum brasilense Mep/Amt proteins where shown to be necessary for growth when the external concentration of the diffusive ammonium form (NH3) becomes limiting. Ammonium transporters also play an important role in pseudohyphal differentiation in yeast and efficient symbiotic interaction between Rhizobium etli and its host plant. In most bacteria, NH4+ transport appears to be a uniport mechanism driven by the membrane potential, but, depending on the organism, a different mode of ammonium uptake may be operating. Current knowledge offers the basis to investigate further the physiological role of ammonium transporters in the natural habitat of organisms and their importance in plant–bacteria interactions.

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