Partial purification and characterization of L-myo-inositol-1-phosphate synthase of pteridophytic origin

L-myo-InositoL-1- phosphate synthase from bryophytes: purification and characterization of the enzyme from Lunularia cruciata (L.) Dum

“…The K m value for G-6-P, as determined by Lineweaver-Burk plot was 0.80 mM which is comparable to the same for the pteridophytic enzyme having a value of 0.83 (Chhetri et al, 2006a). The V max value of this bryophytic enzyme was calculated as 2.80 mM as against 1.6 mM for the yeast enzyme (Donahue and Henry, 1981b) and 1.42 mM for the pteridophytic enzyme (Chhetri et al 2006a). Though this value differs widely from other plant species, it corresponds to the V max value of 2.95 reported for Taxus baccata (Chhetri and Chiu, 2004).…”

“…The reaction rate was found to increase linearly with respect to G-6-P up to a concentration of 4mM. The K m value for G-6-P, as determined by Lineweaver-Burk plot was 0.80 mM which is comparable to the same for the pteridophytic enzyme having a value of 0.83 (Chhetri et al, 2006a). The V max value of this bryophytic enzyme was calculated as 2.80 mM as against 1.6 mM for the yeast enzyme (Donahue and Henry, 1981b) and 1.42 mM for the pteridophytic enzyme (Chhetri et al 2006a).…”

“…8.00 mM for the yeast enzyme (Donahue and Henry, 1981b) and and 0.44 for the pteridophytic enzyme (Chhetri et al 2006a). The V max value of NAD + for the L. cruciata MIPS was found to be 1.21 mM which is comparable to that of yeast having a value of 1.14 mM (Donahue and Henry, 1981b) but different from those of pteridophytic enzyme which exhibits a V max value of 1.80 mM (Chhetri et al, 2006a).…”

“…The MIPS reaction has been reported from archea (Chen et al 2000); bacteria Mande, 1999, 2000); protozoa (Lohia et al 1999); animals (Maeda and Eisenberg, 1980;Mauck et al, 1980;Biswas et al, 1981); humans (Adhikari and Majumder, 1988) and plants. Among plants the occurrence of MIPS has been described and characterized from algae (Dasgupta et al, 1984;RayChaudhuri et al, 1997); fungi (Donahue and Henry, 1981a,b;Escamilla et al 1982;Dasgupta et al 1984); pteridophytes (Chhetri et al 2005(Chhetri et al , 2006a; gymnosperm (Gumber et al, 1984;Chhetri and Chiu, 2004) and angiosperm (Loewus and Loewus, 1971;Johnson and Sussex, 1995;Johnson and Wang, 1996;RayChaudhuri et al, 1997). The present study is the first report detailing the partial purification and characterization of MIPS from a bryophyte, Lunularia cruciata occurring in the Darjeeling hills of Eastern Himalayas.…”

Isolation, partial purification and biochemical characterization of chloroplastic L-myo-inositol-1-phosphate synthase from a macro alga Enteromorpha intestinalis under high salinity

“…Since the enzyme did not exhibit any activity in absence of NAD + , it can be safely concluded that the plastidial MIPS from E. intestinalis did not possess any 'built in' NAD + in its molecular architecture, unlike the MIPS obtained from mammalian adult brain (Adhikari, Majumder 1983) and from Euglena gracilis (Dasgupta et al 1984). Our results are however in complete agreement with the reports published earlier (Chettri et al 2006a;2006b;Basak et al 2012). The plastidial MIPS exhibited a temperature optima of 35 °C, which is also in complete congruence with majority of the published reports sans a few where a lower temperature maxima for MIPS has been recorded (Chettri et al 2005;2006a;2009).…”