• KSBB Journal
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• v.19 no.6 s.89
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• pp.489-493
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• 2004

The hydrolysis characteristics of various fatty acids composing the fish oil was investigated for function of acyl chain specificities using Lipase-OF 360,000 from Candida cylindracea. The hydrolysis of fatty acids decreased with the increase of the number of carbon and double bond in the fatty acids, in case that the number of double bond and the position of the first double bond from the methyl group of fatty acids were the same. The position of the first double bond was found to be an acyl chain specificity of Lipase-OF 360,000 for the hydrolysis of fish oil. Lipase-OF 360,000 also showed the another acyl chain specificity that the increase of double bond of fatty acids, having the same number of carbon and the position of double bond, brought about the decrease of hydrolysis.

• Journal of Microbiology and Biotechnology
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• v.32 no.7
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• pp.949-954
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• 2022

The lipolytic yeast Candida aaseri SH14 contains three Acyl-CoA oxidases (ACOXs) which are encoded by the CaAOX2, CaAOX4, and CaAOX5 genes and catalyze the first reaction in the β-oxidation of fatty acids. Here, the respective functions of the three CaAOX isozymes were studied by growth analysis of mutant strains constructed by a combination of three CaAOX mutations in minimal medium containing fatty acid as the sole carbon source. Substrate specificity of the CaAOX isozymes was analyzed using recombinant C. aaseri SH14 strains overexpressing the respective genes. CaAOX2 isozyme showed substrate specificity toward short- and medium-chain fatty acids (C6-C12), while CaAOX5 isozyme preferred long-chain fatty acid longer than C12. CaAOX4 isozyme revealed a preference for a broad substrate spectrum from C6-C16. Although the substrate specificity of CaAOX2 and CaAOX5 covers medium- and long-chain fatty acids, these two isozymes were insufficient for complete β-oxidation of long-chain fatty acids, and therefore CaAOX4 was indispensable.

• Journal of Microbiology and Biotechnology
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• v.28 no.4
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• pp.597-605
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• 2018

Acyl-CoA oxidases (ACOXs) play important roles in lipid metabolism, including peroxisomal fatty acid ${\beta}$-oxidation by the conversion of acyl-CoAs to 2-trans-enoyl-CoAs. The yeast Yarrowia lipolytica can utilize fatty acids as a carbon source and thus has extensive biotechnological applications. The crystal structure of ACOX3 from Y. lipolytica (YlACOX3) was determined at a resolution of $2.5{\AA}$. It contained two molecules per asymmetric unit, and the monomeric structure was folded into four domains; $N{\alpha}$, $N{\beta}$, $C{\alpha}1$, and $C{\alpha}2$ domains. The cofactor flavin adenine dinucleotide was bound in the dimer interface. The substrate-binding pocket was located near the cofactor, and formed at the interface between the $N{\alpha}$, $N{\beta}$, and $C{\alpha}1$ domains. Comparisons with other ACOX structures provided structural insights into how YlACOX has a substrate preference for short-chain acyl-CoA. In addition, the structure of YlACOX3 was compared with those of medium- and long-chain ACOXs, and the structural basis for their differences in substrate specificity was discussed.

• Journal of the Korean Chemical Society
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• v.40 no.9
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• pp.630-634
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• 1996

In order to explore a substrate specificity for cabbage phospholipase D, we examined the PLD reactivity toward the phosphatidylcholines with different chain length of acyl groups. The selected acyl chains were the saturated fatty acid of $C_8:0,\;C_{12}:0,\;C_{16}:0,\;C_{20}:0$. The reactivity of these phospholipids were dependent largely on the ratio of PC : SDS. The PC : SDS ratio showing the optimal PLD activity were found to be 1:1.4, 1:2.2, 1:2.5, and 1:3.6 respectively as the increase of the acyl chain length. Likewise the optimum temperature for the maximal PLD activity were altered markedly to 25$^{\circ}C$, 30$^{\circ}C$, 35$^{\circ}C$, 45$^{\circ}C$ when the length of acyl chains increased. On the contrary the pH and concentration of $Ca^{2+}$ necessary for the optimum PLD activity were not altered significantly. The kinetic parameter $V_{max}$ for short acyl chain substrate was greater than the values for the longer acyl chain, which indicates the fastest rate of hydrolysis. By the same token, the reactivity of longer chain substrate became slower for the hydrolysis activity.

• KSBB Journal
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• v.13 no.1
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• pp.90-95
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• 1998

Experiments on the process development for the concentration of polyunsaturated fatty acid (PUFAs) such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) from fish oil by using acyl chain specificity of Candida cylindracea lipase were performed. Five kinds of oils were hydrolyzed with Candida cylindracea lipase. Among then, Candida cylindracea lipase just had low activity on the PUFAs-rich fish oil. After the hydrolysis of fish oil, free fatty acid was removed and fatty acid components of glyceride mixtures were analyzed. When the hydrolysis was about 70%, the DHA content in the glyceride mixture was about three times more than that in the original fish oil. The EPA and stearidonic acid contents in the glyceride mixtures, however, were similar to that of the original fish oil. In this work, these results showed that the concentration process of PUFAs by using the acyl chain specificity of Candida cylindreacea lipase was effective in producing glycerides that contained a high concentration of PUFAs in good yield.

• Applied Biological Chemistry
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• v.41 no.4
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• pp.235-240
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• 1998

The myristoyl-acyl carrier protein (ACP) specific thioesterase from Iris tectorum was purified to a considerable homogeneity and characterized. The enzyme was eluted with a considerable stability by double-gradients using Triton X-100 and low ionic KCl or Na-phosphate through DEAE-52, Octyl-Sepharose, Q-Sepharose, and hydroxyapatite chromatoraphy. SDS-PAGE analysis showed a single band of 39 kDa. The native molecular weight was estimated to be 82 kDa by Sephacryl S-200 chromatography, indicating that the enzyme was a dimer. The thioesterase showed a chain-length specificity to myristoyl-ACP in preference to other-ACPs. The enzyme activity decreased by 1.0 mM myristate to about 27% of the original activity, whereas the remaining activity with decanoate was about 90%. The purified thioesterase was inhibited by myristoyl-CoA more than by myristate, suggesting that the myristoyl-AGP thiolesterase might be controlled by myristic acid and/or a subsequent product myristoyl-CoA. In addition, some biochemical characteristics of the enzyme were described.

• Korean Journal of Microbiology
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• v.50 no.2
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• pp.128-136
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• 2014

Acyl homoserine lactone (AHL) lactonase has been proved to be the AHL-degrading enzyme with the highest substrate specificity for AHL molecules and has shown a considerable potential as low-cost and efficient quorum quenching (QQ) technique. However, few studies focused on its inhibitory effect on biofilm formation which is also a quorum sensing (QS)-regulated phenomenon. In this study, QQ activity of six isolates from biofouled reverse osmosis membranes was studied using Chromobacterium violaceum CV026 and Agrobacterium tumefaciens NTL4 as biosensors under various conditions. All of the isolates belonged to the genus Bacillus and showed QQ activity regardless of the acyl chain length or substitution of AHL molecule. The isolates were capable of significantly inhibiting biofilm formation (46.7-58.3%) by Pseudomonas aeruginosa PAO1 and produced heat-sensitive extracellular QQ substances. The LC-MS analysis of the QQ activity of a selected isolate, RO1S-5, revealed the degradation of N-(3-oxododecanoyl)-L-homoserine lactone (3-oxo-C12 AHL) and the production of corresponding acyl homoserine (3-oxo-C12-HS), which indicated the activity of AHL lactonase. The broad AHL substrate range and high substrate specificity suggested that the isolate would be useful for the control of biofilm-related pathogenesis and biofouling in industrial processes.

• Journal of Microbiology and Biotechnology
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• v.9 no.5
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• pp.624-630
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• 1999

In order to investigate the position of various fatty acids attached to glycerol and the specificity of Lipolase-100T, hydrolysis of fish oil was carried out with Lipolase-100T derived from Aspergillus oryzae. The amounts of free fatty acids produced from triglyceride, 1,2(2,3)-diglyceride, 1,3-diglyceride, and 2-monoglyceride and conversion rates of 1,2(2,3)-diglyceride to 1,3-diglyceride and 2-monoglyceride to 1(3)-monoglyceride were also calculated. The ratio of 1,2-diglyceride content to 1,3-diglyceride was higher than 70 in the early period of hydrolysis. The fatty acid content of the glyceride mixture after 72 h of hydrolysis was compared with that of fish oil, and it was found that polyunsaturated fatty acids such as C16:4, C20:4 n-3, C20:5 n-3, C21:5 n-3, C22:5 n-3 and C22:6 n-3 were located in the 2-position of glycerol. Material balance of each component in the hydrolysis system was written to obtain a set of simultaneous linear equations. The theoretical quantity of free fatty acids produced from triglyceride, 1,2-diglyceride, 1,3-diglyceride, and monoglyceride, respectively, were calculated by solving the linear equation system. The conversion rate of 1,2(2,3)-diglyceride to 1,3-diglyceride and that of 2-monoglyceride to 1(3)-monoglyceride were also obtained. The results showed that the migration rate of 1,2(2,3)-diglyceride to 1,3-diglyceride was higher than the hydrolysis rate of 1,2(2,3)-diglyceride to 2-monoglyceride and the conversion rate of 2-monoglyceride to 1(3)-monoglyceride was extremely low.

• Journal of Genetic Medicine
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• v.4 no.1
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• pp.53-63
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• 2007

Purpose : Tandem mass spectrometry (MS/MS) is effective screening test for inherited metabolic diseases. In this study, we estimate potential costs and benefits of using tandem mass spectrometry (MS/MS) to screen new borns for inherited metabolic diseases (phenylketonuria, BH4 deficiency, citrullinemia, maple syrup urine disease, propionic aciduria, isovaleric aciduria, glutaric aciduria type 1, LCHAD deficiency) in Korea. Methods : From April 2001 to March 2004, 79,179 new borns were screened for amino acid disorders, organic acid disorders, and fatty acid oxidative disorders. Twenty-eight new borns were diagnosed with one of the metabolic disorder and the collective estimated prevalence amounted to 1 in 2,800 with a sensitivity of 97.67%, a specificity of 99.28%, a recall rate of 0.05%, and a positive preditive value of 6.38%. We calculated and compared the total costs in case when neonatal screening on pheny lketonuria, BH4 deficiency, citrullinemia, maple syrup urine disease, propionic aciduria, isovaleric aciduria, glutaric aciduria type 1, LCHAD deficiency is implemented, and when not. Results : If the neonatal screening on pheny lketonuria, BH4 deficiency, citrullinemia, maple syrup urine disease, propionic aciduria, isovaleric aciduria, glutaric aciduria type 1, LCHAD deficiency is implemented, total benefits far exceed costs at a ratio of 1.40:1. Conclusion : Although, this study only concerns the monetary aspects of the neonatal screening, tandem mass spcetrometry for neonatal screening is cost-effective compared with not screening. The study appears to support the introduction of tandem mass spectrometry into a Korea neonatal screening programme for inherited metabolic diseases.