Human CHD2 peptide

Background: Enterocytozoon bieneusi is a common opportunistic pathogen found in both humans and animals. As companion animals live in close contact with human being, they may act as a zoonotic reservoir and play an important role in transmitting this parasite to humans. We evaluated the prevalence, genotypic diversity and zoonotic potential of E. bieneusi in dogs and cats in eastern China during Apr to Dec 2013. Methods: Fecal specimens from 315 dogs and 143 cats from veterinary hospitals in eastern China were examined in 2015 by internal transcribed spacer (ITS)-based PCR. Results: E. bieneusi was detected in 8.6% of canine and in 1.4% of feline samples. Seven genotypes of E. bieneusi were identified, including four known genotypes (PtEb IX, EbpC, Type IV and D) and three novel genotypes, named CHD1, CHD2 and CHD3. The dominant genotype in dogs was PtEbIX (59.3%; n=16/27). Five (CHD1, EbpC, CHD2, D and Type IV) of the seven genotypes were in the so-called zoonotic group 1, whereas genotypes PtEbIX belonged to the dog-specific group and genotypes CHD3 were placed in group 2. Conclusion: Dogs are predominately infected with host-specific genotypes of E. bieneusi, and the finding of several zoonotic genotypes in dogs and cats reminds us of potentially zoonotic transmission of microsporidiosis.

We demonstrate the feasibility of the measurement of up to nine deuterium spin relaxation rates in (CHD2)-C-13 and (CH2D)-C-13 methyl isotopomers of small proteins. In addition to five measurable H-2 relaxation rates. in a (CH2D)-C-13 methyl group (Millet, O.; Muhandiram, D. R.; Skrynnikov, N. R; Kay, L. E. J. Am. Chem. Soc. 2002, 124, 6439-48), the measurement of additional four rates of (nearly) single-exponentially decaying magnetization terms in methyl groups of the (CHD2)-C-13 variety is reported. Consistency relationships between H-2 spin relaxation rates measured in the two different types of methyl groups are derived and verified experimentally for a subset of methyl-containing side chains in the protein ubiquitin. A detailed comparison of methyl-bearing side-chain dynamics parameters obtained from relaxation measurements in (CH2D)-C-13 and (CHD2)-C-13 methyls of ubiquitin at 10, 27, and 40 degrees C reveals that transverse H-2 relaxation rates in (CHD2)-C-13 groups are reliable and accurate reporters of the amplitudes of methyl 3-fold axis motions (S-axis(2)) for protein molecules with global molecular tumbling times tau(C)> similar to 9 ns. For smaller molecules, simple correction of transverse H-2 relaxation rates in (CHD2)-C-13 groups is sufficient for the derivation of robust measures of order. Residue-specific distributions of S-axis(2) are consistent with atomic-detail molecular dynamics (MD) results. Both (CHD2)-C-13- and (CH2D)-C-13-derived S-axis(2) values are in good overall agreement with those obtained from 1 mu s MD simulations at all the three temperatures, although some differences in the site-specific temperature dependence between MD- and H-2-relaxation-derived S-axis(2) values are observed.