Hydroxy fatty acids strain

From Nocardia strains several closely related compounds (nocobactins, formo-bactin, amamistatins) were isolated that contain three typically Fe " binding sites, two hydroxamate units, and ahydroxyphenyloxazole stmcture (cf. Sect. 3.2 below). The C-terminus is A-hydroxy-cyc/o-Lys bound to a long chain 3-hydroxy fatty acid, whose hydroxy group is esterified by A -acyl-A -hydroxy-Lys, the a-amino group of which is bound to 2-o-hydroxyphenyl-5-methyl-oxazole-4-carboxylic acid (Table 4). For the amamistatins the configuration of the cyclic lysine was determined as L, the open one as d, and that of C-3 of the fatty acid as (S). The involvement in the iron metabolism was not investigated. 

The lipid material precipitated upon mild acid treatment of the Boivin-extracted lipopolysaccharide is here termed a lipoidal precipitate. The fatty-acid profile (Table IV) of hydrolyzates of this material shows little variation between the seven lmmunotype strains. If the original lipopolysaccharides are first treated by phenol—water extraction, and the resultant materials then subjected to hydrolysis to release the lipid, the composition of the latter is significantly different it corresponds closely to the classic composition expected for lipid A. It is noteworthy that material extracted by the phenol—water (Westphal) method is rich in the Csaturated acid and in the hydroxy fatty acids having ten and twelve carbon atoms, whereas the and C g saturated acids present in the lipoidal precipitate, as prepared by the Boivin procedure, are absent or present at much lower levels in the lipid prepared by the Westphal procedure -9). It... 

It has been reported that a microbial isolate, Flavobacterium sp. strain DS5, produced 10-ketostearic acid (10-KSA) from oleic acid in 85% yield (Hou, 1994a). The purified product was white, plate-like crystals melting at 79.2°C. A small amount of 10-hydroxystearic acid (10-HSA) was also produced during the bioconversion, suggesting that oleic acid is converted to 10-KSA via 10-HSA, and the enzyme catalyzing the hydration is C-10 positional specific (Hou, 1994b, 1995). The DS5 bioconversion products from oleic, linoleic, a-linolenic, and y-linolenic acid are all 10-hydroxy fatty acids. The optimum time, pH, and temperature for the production of 10-KSA have been reported in flask... 

Since Wallen et al. (1962) reported the first bioconversion of oleic acid to 10-hydroxystearic acid by a Pseudomonad, microbial conversions of unsaturated fatty acids from different substrates by various microbial strains have been widely exploited to produce new, value-added products. Among the unsaturated fatty acids used for microbial production of hydroxy fatty acids, three (oleic, linoleic, and linolenic acids) were well studied as substrates to produce mono-, di-, and trihydroxy fatty acids. Recently, a bacterial strain Pseudomonas aeruginosa NRRL B-18602 (PR3) has been studied to produce hydroxy fatty acids from several fatty acid substrates. In this review, we introduce the production of hydroxy fatty acids from their corresponding fatty acid substrates by P. aeruginosa PR3 and their industrially valuable biological activities. 

Based on the postulated common metabolic pathway involved in DOD and TOD formation by PR3, it was assumed that palmitoleic acid containing a singular C9 cis double bond (a common structural property shared by oleic and ricinoleic acids), could be utilized by PR3 to produce hydroxy fatty acid. Bae et al. (2007) reported that palmitoleic acid could be utilized as a substrate for the production of hydroxy fatty acid by PR3. Structural analysis of the major product produced from palmitoleic acid by PR3 confirmed that strain PR3 could introduce two hydroxyl groups on carbon 7 and 9 with shifted migration of 9-cis double bond into 8-tram configuration, resulting in the formation of 7,10-dihydroxy-8( )-hexadecenoic acid (DHD) (Fig. 31.3).The time course study of DHD production showed that DHD formation was time-dependently increased, and peaked at 72 h after the addition of palmitoleic acid as substrate. However, production yield of DHD (23%) from palmitoleic acid was relatively low when compared to that of DOD (70%) from oleic acid (Hou and Bagby, 1991). 

Various unsaturated fatty acids were efficiently used for the production of various hydroxy fatty acids by bacterial strain P. aeruginosa PR3. Among those unsaturated fatty acids, oleic acid, ricinoleic acid, linoleic acid, palmitoleic acid,... 

The second fermentation was developed using yeast strains, such as Yarrowia lipolytica ATCC 34088, that has limited P-oxidation abilities. The recovered hydroxy fatty acids were fed into a new fermenter and sterilized with other ingredients before inoculation with Y. lipolytica culture. Y. lipolytica converted C-18 10-hydroxy fatty acids to the corresponding lactone intermediates, 4-hydroxy C12 fatty acids via a limited P-oxidation. The fermentation was usually terminated at the point of a maximum accumulation of lactone intermediates, at the concentration of 5 g/L in the fermentation broth. After the fermentation process was complete, the lactone intermediates were lactonized at a pH in the range of 3-5 and at a temperature of >100°C. The resulting lactones were recovered and purified from the fermentation broth by solvent extraction followed by fractional distillation. 

Plusbacin Aj (21) and the derivatives A2-A4 and B1-B4 are lipodepsipeptides isolated from a strain numbered PB-6250 related to the genus Pseudomonas obtained from a soil sample collected in the Okinawa Pref., Japan [56]. These compounds contain arginine residue and lactone linkage with characteristic 3-hydroxy fatty acids [57] (Figure 10.6). Plusbacin A3 (22) showed inhibitory activity against methicilhn resistant Staphylococcus aureus [56,58]. Recent total synthesis of this compound was reported and the absolute configuration of the lactone residue was determined as R [59]. 

Most of the mcl-PHA production strains - with the exception of Pseudomonas putida GPol - accumulate alkanoic mcl-PHA also from unrelated carbon substrates through the fatty acid de novo synthesis pathway. Consequently, glucose may result in polymers containing (R)-3-hydroxy fatty acids with even carbon numbers, e.g., (R)-3-hydroxydecanoate, (R)-3-hydroxyoctanoate, (R)-3-hydroxyhexanoate,... 

LPS with endotoxic properties is not confined to pathogens. Whole cells or cell extracts from commensal organisms often show the same degree of biological activity as similar extracts or killed whole cells from a pathogenic strain. By contrast the potency of lipid A varies with source. Despite the severity of infections caused by them, brucellae and yersiniae possess LPS of relatively low toxicity. Similarly Pseudomonas aeruginosa lipid A is less toxic than that derived from Enterobacteriaceae. This is thought to be a result of the predominance of 12 carbon 3-hydroxy fatty acid substituents... 

Glykenins, a family of related antibiotic substances isolated from a Basidiomycetes strain, are oligosaccharide derivatives of hydroxy fatty acids, e.g., compound (47). ... 

A strain of B. circulans produces a broad spectrum antibiotic designated as EM 49. This antibiotic is a mixture of closely related lipopeptides which contain five DAB residues out of eight amino acids like the octapeptins. The structure of the peptide moiety of EM 49 is identical with that of octapeptin (Table 8). The fatty acids of EM 49 are 3-hydroxy fatty acids with 10 or 11 carbon atoms. They were identified as 3-hydroxy-8-methylnonanoic acid, 3-hydroxydecanoic acid and 3-hydroxy-8-methyldecanoic acid (752). 

Strain ALA2 converted y-linolenic acid (18 3 all ds-6,9,12) to several products including 12,17 13,17-diepoxy-6,9-octadecadienoic acid 12,13,17-trihydroxy-6(Z),9(Z)-octadecadienoic acid and 12-hydroxy-13,16-epoxy-6(Z),9(Z)-octadecadienoic acid as depicted in the top half of Figure 16.2 (Hosokawa et al, 2003a). Strain ALA2 also converted the substrate arachidonic acid (20 4 all civ-5,8,11,13) to cyclic and trihydroxyl fatty acids as reported previously (Hosokawa et al., 2003a). These reactions resulted in compounds 14,19 15,19-diepoxy-5(Z),8(Z),ll(Z)-eicosatrienoic acid 14-hydroxy-15,18-epoxy-5(Z),... 

Of interest is a unique alternative biosynthetic pathway for CLA. Ogawa et al. (2001) reported that a strain of Lactobacillus acidophilus, under micro-aerobic conditions, produced 1O-hydroxy-cA-12-octadcccnoic acid and 10-hydroxy-trans-12-octadecenoic acid as intermediates in the synthesis of cis-9, trans-11 and trans-9, cis-11 18 2. The conversion was induced by presence of linoleic acid, and a high yield of CLA was reported. Hudson et al. (1998, 2000) showed that lactic acid bacteria, including Lactobacillus, Pediococcus, and Streptococcus species, are the major unsaturated fatty acid hydrating bacteria in the rumen, converting oleic acid to 10-hydroxy stearic acid and linoleic acid to 10-hydroxy-12-octadecenoic acid and 13-hydroxy-9 octadecenoic acid. Thus, potentially, CLA may be produced also in the rumen from linoleic acid by pathways other than the classic isomerase described by Kepler et al. (1966). 

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