Gut Microorganisms and Autism: the Latest Research

LPS and Autism

LPS and Mercury

Treatments for LPS

LPS and Behavior

LPS and Detox

LPS and the Brain LPS and Thyroid LPS and GI System LPS and Immunity Other Effects of LPS
LPS and Inflammation LPS and Opioids LPS and Oxidative Stress LPS and Leaky Gut LPS and Candida
Anorexia and LPS NF-κB and LPS Mitochondria and LPS Liver and LPS Ammonia and LPS
Hypoglycemia and LPS Kidney and LPS Allergy and Bacteria Copper, Zinc and LPS Glutathione and LPS

How LPS Induces Mitochondrial Disease

Important Words

Lipid A is a part of LPS. (See proof at bottom of this webpage) Endotoxin and lipopolysaccharide are names for LPS.

View this article in PubMed
1: J Bacteriol. 1972 Oct;112(1):268-75.

Site of action of lipid A on mitochondria.

Kato M.

Lipopolysaccharide (LPS) of a number of gram-negative bacteria affected mitochondrial respiration and phosphorylation when it was preincubated with the mitochondrial suspension. The structural part responsible for this activity of LPS is the lipid moiety (lipid A), because the lipid A prepared from either the LPS of Escherichia coli or the endotoxic glycolipid of a heptose-less mutant (R595) of Salmonella minnesota affected mitochondrial oxidative phosphorylation as did LPS, whereas the polysaccharide moiety was inactive. Preincubation of the mitochondrial suspension with lipid A resulted in (i) inhibition of respiration and accompanying phosphorylation in the presence of either succinate or a number of reduced nicotinamide adenine dinucleotide-linked substrates, (ii) decrease of respiratory control, (iii) inhibition of the transfer of electrons at coupling site II without decrease of efficiency of phosphorylation, and the uncoupling at coupling site III, and (iv) stimulation of adenosine triphosphatase and the inhibition of 2,4-dinitrophenol-induced adenosine triphosphatase.

PMID: 4263402 [PubMed - indexed for MEDLINE]

View this article in PubMed
1: Infect Immun. 1979 Aug;25(2):664-71.

Action of bacterial endotoxin and lipid A on mitochondrial enzyme activities of cells in culture and subcellular fractions.

McGivney A, Bradley SG.

Escherichia coli O127:B8 lipopolysaccharide (LPS), prepared by the Westphal procedure, caused a marked decrease in the activities of mitochondrial malate dehydrogenase, succinate dehydrogenase, and adenylate kinase in African green monkey kidney (Vero) cells and primary cultures of mouse liver cells within 2 h after exposure to 10 micrograms of LPS/ml of culture medium. These three enzyme activities leaked into the supernatant fraction, and cytochrome oxidase activity was lost from the mouse liver mitochondrial particulate fraction within 45 min after exposure to 10 micrograms of LPS/mg of protein. Loss malate dehydrogenase activity from isolated mitochondria was also accelerated by LPS from E. coli O26:B6 (Boivin preparation) or Salmonella typhosa O901 (Westphal preparation), and by lipid A from Salmonella minnesota or Shigella sonnei. In addition, LPS and lipid A inhibited state 3 respiration by isolated mitochondria with attendant loss of respiratory control, but adenosine 5'-diphosphate/O ratios were relatively unchanged. Impaired mitochondrial function is an early event after exposure to biologically relevant amounts of LPS or lipid A.

PMID: 114491 [PubMed - indexed for MEDLINE]

Proof that Lipid A is a part of LPS.

View this article in PubMed
1: Annu Rev Biochem. 2002;71:635-700. Epub 2001 Nov 9.

Lipopolysaccharide endotoxins.

Raetz CR, Whitfield C.

Department of Biochemistry, Duke University Medical Center, Durham, North Carolina 27710, USA.

Bacterial lipopolysaccharides (LPS) typically consist of a hydrophobic domain known as lipid A (or endotoxin), a nonrepeating "core" oligosaccharide, and a distal polysaccharide (or O-antigen). Recent genomic data have facilitated study of LPS assembly in diverse Gram-negative bacteria, many of which are human or plant pathogens, and have established the importance of lateral gene transfer in generating structural diversity of O-antigens. Many enzymes of lipid A biosynthesis like LpxC have been validated as targets for development of new antibiotics. Key genes for lipid A biosynthesis have unexpectedly also been found in higher plants, indicating that eukaryotic lipid A-like molecules may exist. Most significant has been the identification of the plasma membrane protein TLR4 as the lipid A signaling receptor of animal cells. TLR4 belongs to a family of innate immunity receptors that possess a large extracellular domain of leucine-rich repeats, a single trans-membrane segment, and a smaller cytoplasmic signaling region that engages the adaptor protein MyD88. The expanding knowledge of TLR4 specificity and its downstream signaling pathways should provide new opportunities for blocking inflammation associated with infection.

PMID: 12045108 [PubMed - indexed for MEDLINE]