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The gene encoding a group 3 late embryogenesis abundant (LEA) protein was cloned from callus of the drought-tolerant grass Pogonatherum paniceum. Three alternatively spliced transcripts of this gene were amplified by RT-PCR. According to the bioinformatics analysis, the gene contained three exons and two introns. The PpLEA3.1 transcript which was the most abundant one in P. paniceum contained all three exons, and the PpLEA3.2 transcript lacked fragments of the first two exons which encoded a 41-amino acid-long region of the PpLEA3 protein. The PpLEA3.3 transcript retained the second intron. The three splicing patterns resulted in changes in the number of repeats of an 11-amino acid motif, hydropathy and the predicted 3-dimensional structure. When expressed in Escherichia coli, the three proteins differentially affected growth responses to salt, cold and heat stress. These results confirmed that the complete motif repeat structures and an appropriate hydrophilic/hydrophobic balance are important for the LEA protein in providing protection against various forms of stresses.

Four novel coordination compounds of formula [M(Hoxonato)]n·xnH2O (1M⊂xH2O; H3oxonic: 4,6-dihydroxy-1,3,5-triazine-2-carboxylic acid; M = Mn, Co, Zn, x = 3; M = Ni, x = 4) were prepared and characterized. The isomorphous Mn(II), Co(II) and Zn(II) derivatives contain densely packed 1D helical chains. To increase the dimensionality of these systems, the [M(Hoxonato)]n secondary building unit was coupled to rod-like N,N′-spacers, allowing the isolation of [Zn(Hoxonato)(bpy)0.5]n·nH2O (2Zn⊂H2O; bpy: 4,4′-bipyridine) and [Ni(Hoxonato)(bpy)]n·6nH2O (3Ni⊂6H2O). The [M(Hoxonato)]n chains are pillared by the bpy spacers within 2D corrugated layers in the former, into 2D rectangular grid layers in the latter. The thermal behavior of all the species was investigated by coupling simultaneous thermal analysis and thermodiffractometry. Static gas adsorption measurements with N2 (77 K) and CO2 (273 K) revealed that activated 3Ni⊂6H2O possesses permanent porosity. Dynamic gas separation studies towards CH4:CO2 mixtures (0.73:0.27 v/v, 273 K) proved that this system is able to selectively capture CO2 up to 0.16 mmol per gram of material.