scholarly journals Regulation of membrane lipid synthesis in Escherichia coli. Accumulation of free fatty acids of abnormal length during inhibition of phospholipid synthesis.

1975 ◽  
Vol 250 (15) ◽  
pp. 5835-5840 ◽  
Author(s):  
J E Cronan ◽  
L J Weisberg ◽  
R G Allen
Keyword(s):  
Escherichia Coli ◽  
Fatty Acids ◽  
Free Fatty Acids ◽  
Lipid Synthesis ◽  
Membrane Lipid ◽  
Phospholipid Synthesis

scholarly journals Genome-scale target identification in Escherichia coli for high-titer production of free fatty acids

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Lixia Fang ◽  
Jie Fan ◽  
Shulei Luo ◽  
Yaru Chen ◽  
Congya Wang ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Fatty Acids ◽  
Free Fatty Acids ◽  
Stress Responses ◽  
Metabolic Networks ◽  
Target Identification ◽  
High Titer ◽  
Cell Factory ◽  
Microbial Cell Factory ◽  
Ffa Metabolism

AbstractTo construct a superior microbial cell factory for chemical synthesis, a major challenge is to fully exploit cellular potential by identifying and engineering beneficial gene targets in sophisticated metabolic networks. Here, we take advantage of CRISPR interference (CRISPRi) and omics analyses to systematically identify beneficial genes that can be engineered to promote free fatty acids (FFAs) production in Escherichia coli. CRISPRi-mediated genetic perturbation enables the identification of 30 beneficial genes from 108 targets related to FFA metabolism. Then, omics analyses of the FFAs-overproducing strains and a control strain enable the identification of another 26 beneficial genes that are seemingly irrelevant to FFA metabolism. Combinatorial perturbation of four beneficial genes involving cellular stress responses results in a recombinant strain ihfAL−-aidB+-ryfAM−-gadAH−, producing 30.0 g L−1 FFAs in fed-batch fermentation, the maximum titer in E. coli reported to date. Our findings are of help in rewiring cellular metabolism and interwoven intracellular processes to facilitate high-titer production of biochemicals.

Histochemical and Morphological Studies of the Lipids in Oogenesis. I. Periplaneta americana

1958 ◽  
Vol s3-99 (47) ◽  
pp. 315-332
Author(s):  
VISHWA NATH ◽  
BRIJ L. GUPTA ◽  
BACHAN LAL
Keyword(s):  
Fatty Acids ◽  
Free Fatty Acids ◽  
Periplaneta Americana ◽  
Lipid Synthesis ◽  
Active Role ◽  
Lipid Bodies ◽  
Acetone Extraction ◽  
Morphological Studies ◽  
Carbohydrate Complex

1. Three kinds of lipid bodies have been described in the oogenesis of the cockroach, Periplaneta americana (i) L1 bodies, present in the earliest oocyte, which persist till the oocyte measures approximately mm and contain phoapholipids only, possibly having more lecithint than cephalins; (ii) L2bodies, which first arise in the oocyte measuring 0.4 mm and have a complete or incomplete sheath of phoapholipida surrounding a medulla of triglycerides (rather highly saturated); (iii) L3 bodies, which are the only type of lipids present in the oocytea measuring more than 0.65 mm and consist of triglycerides only (rather highly saturated). 2. Some of the larger L3 bodies give a ‘ringed’ or ‘crescentic’ appearance in Sudan black when used at room temperatures (12° C to 40° C) but appear mostly solid when this colouring agent is used at 6o° C. 3. Mitochondria, which remain as fine granules throughout the course of oogenesis, contain proteins and phospholipids. They seem to have some lipids which are masked normally but are unmasked after acetone extraction, with a resulting increase in sudanophilia. 4. Yolk globules appear in the oocytes meaauring approximately 0.5 mm. They contain a protein-carbohydrate complex. 5.The bacterioid objects described by earlier workers have been shown to contain phospholipids and free fatty acids. They possibly play an active role in the lipid synthesis of the cell.

scholarly journals Genome-wide targets identification by CRISPRi-Omics for high-titer production of free fatty acids in Escherichia coli

2020 ◽  
Author(s):  
Lixia Fang ◽  
Jie Fan ◽  
Congya Wang ◽  
Yingxiu Cao ◽  
Hao Song
Keyword(s):  
Escherichia Coli ◽  
Fatty Acids ◽  
Free Fatty Acids ◽  
Metabolic Networks ◽  
High Titer ◽  
Cell Structure ◽  
Cell Factory ◽  
Microbial Cell Factory ◽  
Cell Potential ◽  
E Coli

AbstractTo construct a superior microbial cell factory for chemical synthesis, a major challenge is to fully exploit cell potential via identifying and engineering beneficial gene targets in the sophisticated metabolic networks. Here, we develop an approach that integrates CRISPR interference (CRISPRi) to readily modulate genes expression and omics analyses to identify potential targets in multiple cellular processes, enabling systematical discovery of beneficial chromosomal gene targets that can be engineered to optimize free fatty acids (FFAs) production in Escherichia coli. We identify 56 beneficial genes via synergistic CRISPRi-Omics strategy, including 46 novel targets functioning in cell structure and division, and signaling transduction that efficiently facilitate FFAs production. Upon repressing ihfA and overexpressing aidB and tesA’ in E. coli, the recombinant strain LihfA-OaidB results in a FFAs titer of 21.6 g L-1 in fed-batch fermentation, which, to our best knowledge, is the maximum FFAs titer by the recombinant E. coli reported to date.

scholarly journals Energy Metabolism Changes and Dysregulated Lipid Metabolism in Postmenopausal Women

Nutrients ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 4556
Author(s):  
Seong-Hee Ko ◽  
YunJae Jung
Keyword(s):  
Fatty Acids ◽  
Energy Metabolism ◽  
Free Fatty Acids ◽  
Postmenopausal Women ◽  
Visceral Fat ◽  
Metabolic Diseases ◽  
Lipid Synthesis ◽  
Hormonal Changes ◽  
Atp Production ◽  
Adipose Tissue Lipoprotein Lipase

Aging women experience hormonal changes, such as decreased estrogen and increased circulating androgen, due to natural or surgical menopause. These hormonal changes make postmenopausal women vulnerable to body composition changes, muscle loss, and abdominal obesity; with a sedentary lifestyle, these changes affect overall energy expenditure and basal metabolic rate. In addition, fat redistribution due to hormonal changes leads to changes in body shape. In particular, increased bone marrow-derived adipocytes due to estrogen loss contribute to increased visceral fat in postmenopausal women. Enhanced visceral fat lipolysis by adipose tissue lipoprotein lipase triggers the production of excessive free fatty acids, causing insulin resistance and metabolic diseases. Because genes involved in β-oxidation are downregulated by estradiol loss, excess free fatty acids produced by lipolysis of visceral fat cannot be used appropriately as an energy source through β-oxidation. Moreover, aged women show increased adipogenesis due to upregulated expression of genes related to fat accumulation. As a result, the catabolism of ATP production associated with β-oxidation decreases, and metabolism associated with lipid synthesis increases. This review describes the changes in energy metabolism and lipid metabolic abnormalities that are the background of weight gain in postmenopausal women.

Sign in / Sign up

Export Citation Format

Share Document