Polyunsaturated fatty acids in marine bacteria — a dogma rewritten (original) (raw)

Quantitative effects of unsaturated fatty acids in microbial mutants

Biochimica et Biophysica Acta (BBA) - Lipids and Lipid Metabolism, 1977

The ability of a series of 18 carbon acetylenic fatty acids to fulfill the unsaturated fatty acid requirements of Escherichia coli and Saccharomyces cereuisiae was investigated. Despite their high melting points (>4O"C), several isomers of the acetylenic fatty acids were as efficient or more efficient in supporting growth than the analogous fatty acid having a cis-double bond. The efficiencies of the different positional isomers in supporting cell proliferation varied from essentially 0 cells per fmol for the 2-5 and 13-17 isomers to high values when the acetylenic bond was near the center of the chain: e.g. 45 E. coli and 5.5 S. cereuisiae cells/fmol for the 10 isomer. A striking ineffectiveness of the 9 isomer was observed with E. coli. The 7, 8 and 10 isomers were at least lo-fold more efficient than any of the other positional isomers in supporting the growth of E. colt In contrast, the 9 isomer was among the most effective acetylenic fatty acids tested with the yeast mutant. Chromatographic analysis of the extracted lipids indicated that each of the acetylenic isomers tested (except A2 and A3) could be esterified by the prokaryotic and eukaryotic microorganisms. The content of unsaturated plus cyclopropane acids observed when growth ceased in E. coli cultures supplemented with gro~h-limiting concentrations of the acetylenic fatty acids ranged from approx. 15 mol% for the 8 isomer to approx. 35 mol% for the 14 and 17 isomers. The 8-11 isomers were observed to be esterified predominantly at the two position in phosphatidylethanolamine of E. coli and in phosphatidylcholine of S. cereuisiae.

Lipids of Prokaryotic Origin at the Base of Marine Food Webs

Marine Drugs, 2012

In particular niches of the marine environment, such as abyssal trenches, icy waters and hot vents, the base of the food web is composed of bacteria and archaea that have developed strategies to survive and thrive under the most extreme conditions. Some of these organisms are considered -extremophiles‖ and modulate the fatty acid composition of their phospholipids to maintain the adequate fluidity of the cellular membrane under cold/hot temperatures, elevated pressure, high/low salinity and pH. Bacterial cells are even able to produce polyunsaturated fatty acids, contrarily to what was considered until the 1990s, helping the regulation of the membrane fluidity triggered by temperature and pressure and providing protection from oxidative stress. In marine ecosystems, bacteria may either act as a sink of carbon, contribute to nutrient recycling to photo-autotrophs or bacterial organic matter may be transferred to other trophic links in aquatic food webs. The present work aims to provide a comprehensive review on lipid production in bacteria and archaea and to discuss how their lipids, of both heterotrophic and chemoautotrophic origin, contribute to marine food webs.

Biogenesis of Fatty Acids, Lipids and Membranes

2019

This handbook is the unique and definitive resource of current knowledge on the diverse and multifaceted aspects of microbial interactions with hydrocarbons and lipids, the microbial players, the physiological mechanisms and adaptive strategies underlying microbial life and activities at hydrophobic material:aqueous liquid interfaces, and the multitude of health, environmental and biotechnological consequences of these activities.

Chapter 3 Fatty acid and phospholipid metabolism in prokaryotes

Biochemistry of Lipids, Lipoproteins and Membranes, 4th edition, 2002

2-acyl-GPE acyltransferase Carboxyltransferase subunit Biotin carboxy carrier protein Biotin carboxylase Carboxyl transferase subunit Acyl carrier protein Azoreductase Acyl carrier protein synthase CDP-diacylglycerol hydrolase CDP-diacylglycerol synthase Stabilizes mutant CDP-diacylglycerol synthase Cyclopropane fatty acid synthase Cardiolipin synthase Desaturase Diacylglycerol kinase ~-Hydroxydecanoyl-ACP dehydrase [3-Ketoacyl-ACP synthase I Malonyl-CoA : ACP transacylase f3-Ketoacyl-ACP synthase II ~-Ketoacyl-ACP reductase ~-Ketoacyl-ACP-synthase III Enoyl-ACP reductase 1 Enoyl-ACP reductase II EnoyI-ACP reductase III [5-Hydroxyacyl-ACP dehydrase [5-Ketoacyl-CoA thiolase 4-Function enzyme of [5-oxidation: [5-hydroxyacyl-CoA dehydrogenase and epimerase; cis-~-trans-2-enoyl-CoA isomerase and enoyl-CoA hydratase Acyl-CoA symhetase Electron transferring flavoprotein Acyl-CoA dehydrogenase Acyl-CoA dehydrogenase? 2,4-dienoyl-CoA reductase Long-chain fatty acid transport protein

Lipids from heterotrophic microbes: advances in metabolism research

Trends in Biotechnology, 2011

Heterotrophic oleaginous microorganisms are capable of producing over 20% of their weight in single cell oils (SCOs) composed of triacylglycerols (TAGs). These TAGs contain fatty acids, such as palmitic, stearic and oleic acids, that are well-suited for biodiesel applications. Although some of these microbes are able to accumulate SCOs while growing on inexpensive agro-industrial biomass, the competition with plant oil resources means that a significant increase in productivity is desired. The present review aims to summarize recent details in lipid metabolism research and engineering (e.g. direct fatty acid ethyl ester production), as well as culture condition optimization and innovations, such as solid-state or semisolid-state fermentation, that can all contribute to higher productivity and further advancement of the field.

Biosynthesis and regulation of microbial polyunsaturated fatty acid production

Journal of bioscience and bioengineering, 1999

Growing interest in polyunsaturated fatty acid (PUFA) applications in various fields coupled with their significance in health and dietary requirements has focused attention on the provision of suitable sources of these compounds. Isolation of highly efficient oleaginous ...

Polyunsaturated fatty acids in Antarctic bacteria

Antarctic Science, 1993

Thirty eight strains of Antarctic bacteria were screened for the ability to produce polyunsaturated fatty acids(PUFA). Five strainscontainedeicosapentaenoic acid ( 2 0 5~3 ) in the rangeoftrace to 3,3%oftotalfatty acids, and up to 1.4 mg g-' dry weight. Thirteen strains produced polyunsaturates including 18:206,18:3~3,18:4~3 and 20:406 in the range of trace to 7.0% of total fatty acids. Although the data set is currently small, the proportion of Antarctic strains found to produce PUFA's is higher than that found for temperate marine bacteria (and is similar to that recorded for barophilic bacteria). This suggests that the Antarctic environment has naturally selected for bacterial strains capable of maintainingmembrane lipid fluidity by the production of PUFA. Theseresults highlight the potential of Antarctic bacteria for possible consideration in the industrial production of PUFA. The fatty acid composition of Flectobacillus glomeratus is reported and discussed in relation to other closely related Antarctic flavobacteria. Fatty acid composition is also shown to represent an important chemotaxonomic tool to aid with the identification of Antarctic bacteria.