The Lipid Fatty Acids of Proteolytic Clostridia

Elsden, S. R.; Hilton, T Martin G.; Parsley, K. R.; Self, Ron

doi:10.1099/00221287-118-1-115

Cited by 22 publications

(17 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Peaks consistent with the presence of carboxylate anions are shown in Table 1 (6). These findings were generally true irrespective of the outbreak source of the strain.…”

supporting

confidence: 61%

Phospholipid profiles of Clostridium difficile

1996

View full text Add to dashboard Cite

Phospholipid molecular species present in 32 isolates of Clostridium difficile were examined by fast atom bombardment-mass spectrometry in negative-ion mode. This revealed major anions consistent with the expected presence of the following phosphatidylglycerol (PG) analogs: PG(31:2), PG(32:1), PG(33:2), PG(33:1), PG(34:2), and PG(34:1). The major phospholipid molecular species are distinct from those of other bacterial groups examined.Clostridium difficile is the major cause in humans of pseudomembranous colitis and is also implicated in both antibiotic-associated colitis and antibiotic-associated diarrhea (11). Nocosomial acquisition has led to numerous outbreaks of infection in hospitals and in the community (2). The emerging importance of this pathogenic species has stimulated interest in its biochemistry.Analysis of phospholipid constituents of Clostridium spp. by chromatographic approaches has revealed that Clostridium acetobutylicum typically elaborates phosphatidylethanolamine and then phosphatidylglycerol (PG), diphosphatidylglycerol, and unknown phospholipids as its major phospholipids (9). Minor amounts of other phospholipids such as phosphatidic acid and glycerol acetal derivatives of phosphatidylmethylethanolamine plasmalogens have also been described. The three major phospholipids (see above) have also been described in Clostridium butyricum. The latter species also produces phosphatidylmethylethanolamine derivatives. Phosphatidylethanolamine derivatives were not found in Clostridium perfringens (10). In the case of C. difficile, the phospholipid classes present have not been studied.Cellular fatty acid composition of several Clostridium species has been investigated previously (8) by gas chromatographic analysis of carboxylate methyl esters. However, analyses of fatty acids generally have used whole-cell extracts (3) so that fatty acid composition of phospholipid constituents alone is unknown in Clostridium spp.The aim of this study was to obtain detailed information on major phospholipid molecular species of C. difficile.Thirty-two isolates from 11 outbreaks were the gift of E. Kaczmarski, Central Public Health Laboratory, Manchester, United Kingdom. Isolates were grown on 5% horse bloodfastidious anaerobe agar (Lab-M, Bury, United Kingdom) incubated in an anaerobic cabinet (Don Whitley Scientific) at 36ЊC for 48 h. Cells were harvested and washed with phosphate-buffered saline (5), and then suspensions were centrifuged at 3,000 ϫ g for 20 min so that a pellet of cells might be obtained. Cell pellets were frozen and then lyophilized (Modulyo; Edwards High Vacuum), prior to extraction. Extraction and analysis of phospholipids by conventional fast atom bombardment-mass spectrometry (FAB-MS) (7) were performed according to our published methods (4, 5). Because of the high polarity of phospholipids, lipid extraction was performed with methanol-chloroform (2:1 [vol/vol]) rather than with methanol-chloroform (1:2 [vol/vol]), which has commonly been employed for total lipid extraction (3). This results i...

show abstract

“…Peaks consistent with the presence of carboxylate anions are shown in Table 1 (6). These findings were generally true irrespective of the outbreak source of the strain.…”

supporting

confidence: 61%

Phospholipid profiles of Clostridium difficile

1996

View full text Add to dashboard Cite

show abstract

“…We found phosphatidylcholine-like lipid in phospholipids, but its Rf did not coincide with that of authentic sample. The overall fatty acid composition of cells has been investigated in many proteolytic clostridia (21). We expected some difference in the fatty acid composition of C. saccharoperbutylacetonicum from that of those clostridia, since C. saccharoperbutylacetonicum is a strain which produces a high concentration of butanol and acetone, and has some resistance to those solvents.…”

Section: Discussionmentioning

confidence: 99%

Chemical composition of autoplast membrane of Clostridium saccharoperbutylacetonicum.

Ogata

Yoshino

Okuma

et al. 1982

J. Gen. Appl. Microbiol.

View full text Add to dashboard Cite

The chemical composition of bacterial protoplasmic membrane was studied using Clostridium saccharoperbutylacetonicum ATCC 13564. The membrane was prepared from the autoplasts. The purity of prepared membrane was certified by chemical analysis for the existence of diaminopimelic acid due to contaminated cell wall debris and of adenosinetriphosphatase (ATPase) activity in its preparation, and also by electron microscopic observation for the existence of contaminated cell wall debris. The membrane composition was made up of lipid (26 %), protein (65 %), carbohydrate (2%) and nucleic acid (2%). The lipid consisted of neutral lipid (26 %), glycolipid (26%) and phospholipid (48 %). The main composition of phospholipid was phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. The membrane contained 22 kinds of proteins of different molecular weights.Bacterial protoplasts have frequently been used for the preparation of bacterial protoplasmic membrane. It is said that protoplasts produced autolytically are better for the preparation of protoplasmic membrane by eliminating the contamination of non-cellular supplements used for degradation of cell wall. From the advantages of autolytically produced protoplasts, JOSEPH and SHOCKMAN (1) called them "autoplasts," distinguishable from the protoplasts produced by using exogenous lytic enzymes or antibiotics.Clostridium saccharoperbutylacetonicum (ATCC 13564), previously used for acetone-butanol production, autolyses specifically in the presence of sucrose in hypertonic concentration (0.3 -0.5 M) (2, 3). The autolysis, i. e., sucrose-induced autolysis, is useful for the preparation of the protoplasts (autoplasts), the biological and physiological properties of which were investigated (3). We would like to determine composition of membrane prepared from the clostridial autoplasts, because that of clostridia, especially solvent-producing clostridia, is little known. 293

show abstract

“…L. lactis, however, is able to produce low levels of isovaleric acid (less than 3% of the metabolites produced from leucine) (43 The physiological role of production of BC acids in PAB remains to be determined. In clostridia, the ability to convert BCAAs to the corresponding acids is related to the presence of BC fatty acids in lipids (10). In P. freudenreichii, the cellular fatty acids contain high proportions of BC fatty acids, including 34 to 64% anteiso-C 15 (13,24).…”

Section: Discussionmentioning

confidence: 99%

Conversion of l -Leucine to Isovaleric Acid by Propionibacterium freudenreichii TL 34 and ITGP23

Thierry

Maillard

Yvon

2002

Appl Environ Microbiol

View full text Add to dashboard Cite

Several branched-chain volatile compounds are involved in the flavor of Swiss cheese. These compounds are probably produced by enzymatic conversion of branched-chain amino acids, but the flora and the pathways involved remain hypothetical. Our aim was to determine the ability of Propionibacterium freudenreichii, which is one of the main components of the secondary flora of Swiss cheese, to produce flavor compounds during leucine catabolism. Cell extracts and resting cells of two strains were incubated in the presence of L-leucine, ␣-ketoglutaric acid, and cofactors, and the metabolites produced were determined by high-performance liquid chromatography and gas chromatography. The first step of leucine catabolism was a transamination that produced ␣-ketoisocaproic acid, which was enzymatically converted to isovaleric acid. Both reactions were faster at pH 8.0 than at acidic pHs. Cell extracts catalyzed only the transamination step under our experimental conditions. Small amounts of 3-methylbutanol were also produced by resting cells, but neither 3-methylbutanal nor␣-hydroxyisocaproic acid was detected. L-Isoleucine and L-valine were also converted to the corresponding acids and alcohols. Isovaleric acid was produced by both strains during growth in a complex medium, even under conditions simulating Swiss cheese conditions (2.1% NaCl, pH 5.4, 24°C). Our results show that P. frendenreichii could play a significant role in the formation of isovaleric acid during ripening.The development of cheese flavor during ripening results from the enzymatic breakdown of curd components into sapid and aroma compounds (11). Catabolism of branched-chain (BC), aromatic, and S-containing amino acids has recently received attention because these amino acids are precursors of various volatile compounds, such as acids, aldehydes, alcohols, esters, and thiols, which can contribute to the development of flavor or off-flavor in cheese depending on their levels and the type of cheese (7, 23). In Swiss cheese, the following BC compounds have been identified as flavor impact compounds: 3-methylbutanal, 2-methylbutanal, 3-methylbutanoic acid (isovaleric acid), and the ethyl ester of 3-methylbutanoic acid. These compounds are probably produced from enzymatic conversion of BC amino acids (BCAAs), particularly leucine, but the flora and the pathways involved in their formation in Swiss cheese remain unclear. Therefore, a better understanding of the origin of these compounds is needed in order to control and accelerate the formation of cheese flavor.Dairy propionic acid bacteria (PAB) constitute one of the major floras that grow during the ripening of Swiss type cheeses and are commonly used as secondary starters (26). They are involved in formation of the characteristic flavor and openings of Swiss cheese via fermentation of lactate into acetic acid, propionic, acid and CO 2 (18). While the presence of PAB has been associated with the presence of isovaleric acid in controlled-flora Swiss cheese (28), the ability of these organisms to generate fla...

show abstract

The Lipid Fatty Acids of Proteolytic Clostridia

Cited by 22 publications

References 17 publications

Phospholipid profiles of Clostridium difficile

Phospholipid profiles of Clostridium difficile

Chemical composition of autoplast membrane of Clostridium saccharoperbutylacetonicum.

Conversion of l -Leucine to Isovaleric Acid by Propionibacterium freudenreichii TL 34 and ITGP23

Contact Info

Product

Resources

About