Qi, B. et al. The variant 'his-box' of the C18-9-PUFA-specific elongase IgASE1 from Isochrysis galbana is essential for optimum enzyme activity. FEBS Lett. 547, 137-139

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FEBS Letters (Impact Factor: 3.17). 08/2003; 547(1-3):137-9. DOI: 10.1016/S0014-5793(03)00676-8
Source: PubMed


IgASE1, a C18-Delta9-polyunsaturated fatty acid-specific fatty acid elongase component from Isochrysis galbana, contains a variant histidine box (his-box) with glutamine replacing the first histidine of the conserved histidine-rich motif present in all other known equivalent proteins. The importance of glutamine and other variant amino acid residues in the his-box of IgASE1 was determined by site-directed mutagenesis. Results showed that all the variation in amino acid sequence between this motif in IgASE1 and the consensus sequences of other elongase components was required for optimum enzyme activity. The substrate specificity was shown to be unaffected by these changes suggesting that components of the his-box are not directly responsible for substrate specificity.

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Available from: Colin Michael Lazarus, Jan 17, 2014
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    • "In the present study there were similarities in the values obtained for the fatty acids 14:0, 16:0 and 18:1. High levels of the fatty acids 14:0, 16:0 and 18:1 were also previously reported for I. galbana (Qi et al., 2003). Sánchez et al. (2000) reported high percentages of 14:0 tetradecanoic acid (27.8%), 16:0 (20.5%), 18:1 (10.4%), and 22:6 (n-3) /DHA (9.7%) in I. galbana. "
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    • "Qi & R. Hooley, unpublished). AtPAT10C 192 A was made by PCR mutagenesis (Qi et al., 2003) using primer pairs DHHCtoAF and ZFendnsE, and ZFbegK and DHHCtoAR (Table S3). PCR products were ligated in pJET1. "
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