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Gut microbiota (GM) dysbiosis has been linked to obesity and its metabolic complications such as cardiovascular disease (CVD). The risk of developing CVD increases with elevated concentration of serum triacylglycerol (TAG). In a blinded, randomised two-arm parallel human intervention study we have previously found that four weeks of supplementation with Lactobacillus paracasei subsp. paracasei L. casei W8® (L. casei W8) compared to placebo reduced the concentration of TAG in 64 young healthy adults, an effect, likely mediated by a decreased stearoyl- CoA desaturase-1 (SCD1) activity. In the present study we analysed faecal samples obtained during the intervention study to investigate whether this effect was related to the ability of L. casei W8 to colonise the human gut after supplementation of L. casei W8 (1010 cfu daily) as determined by qPCR specific for L. paracasei and L. casei (L. casei group); whether L. casei W8 consumption affected GM composition as determined by 16S rRNA gene targeted 454/FLX amplicon sequencing; and whether these changes were associated with changes in TAG concentration and SCD1 activity. Faecal samples were collected at baseline, after four weeks supplementation and two weeks after the supplementation was ended, and fasting blood samples were collected at baseline and after 4 weeks. Four weeks supplementation with L. casei W8 did not affect the overall composition of the GM; however, an increase in the relative abundance of the L. casei group from 8.48×10-6% of the total GM compared to 2.83×10-3% at baseline (P<0.001) was observed. Two weeks after supplementation ended, the relative abundance of the L. casei group was still increased 14 times compared to before the intervention (P<0.01). However, neither the increase in the abundance of the L. casei group nor overall GM composition correlated with changes in blood lipids or SCD1 activity.

OsIpk and HvIk, inositol phosphate kinases, were cloned from rice (Oryza sativa L. var. indica, IR64) and barley (Hordeum vulgare) respectively.. IP Sequence alignment showed that they belong to the ATP-grasp family, which includes inositol 1,3,4-trisphosphate 5/6-kinase from humans and Arabidopsis. Residues that are binding sites for ATP and coordinate magnesium in absence or presence of inositol phosphate are conserved and in total 23 residues are invariant among the twelve aligned inositol phosphate kinases. The genes were heterologously expressed in Escherichia coli and kinase activity assays with 17 different isomers of inositol mono-/di-/tri-/tetra-/pentaphosphate as well as phytate were performed. The strongest activity for both kinases was observed with Ins(3,4,5,6)P-4, which candidates as the primary substrate for these kinases in plants. Several species-specific differences between the two recombinant Ipks were observed. Rice OsIpk showed detectable kinase activity towards eight different substrates, whereas barley HvIpk showed kinase activity with all the substrates including inositol mono- and bisphosphates. HvIpk showed 3-kinase activity towards the Ins (1,4,5)P-3 substrate and it also interconverted the two substrates Ins(1,3,4,5)P-4 and Ins(1,3,4,6)P-4 by isomerase activity, which was not observed for the rice homologue. Both OsIpk and HvIpk had no detectable 2-kinase activity. Furthermore, the two Ipks showed phosphatase activity towards several inositol phosphates. Expression analysis by RT-PCR demonstrated that the Ipk gene was equally expressed in different tissues and developmental stages. Taken together, these results show that the Ipk kinase plays a significant role in the inositol phosphate interacting network in plants. (C) 2007 Elsevier B.V. All rights reserved.