Population increase of forest birds in the Czech Republic between 1982 and 2003

Capsule Populations of most forest bird species increased between 1982 and 2003, probably due to increased forest cover and changes in forest age-class composition.

Aims To determine population changes of forest birds in the Czech Republic and to determine their possible causes.

Methods Population data were collected via the Breeding Bird Monitoring Programme, which is based on skilled volunteers counting birds at point transects using a standardized technique. Population trends and indices for the period 1982–2003 were calculated for 47 species using log-linear models. Published data on development of forest cover and forest age composition in the Czech Republic were used to indicate environmental change over the same period.

Results Populations of most forest species increased between 1982 and 2003. There was also an increase in forest cover and an increase in the proportion of older forest age-classes. The increase in forest specialist birds was positively correlated with the average increase in forest coverage.

Conclusions The populations of Czech forest birds have increased in the last two decades. This contrasts with widely reported declines of farmland bird populations throughout Europe. The correlation between populations of specialized forest species and extent of forest habitat suggests that changes in land-use are an important factor. However, increasing cover of mature forests could have a similar effect on the populations of specialist species.     

Donor specificity and regioselectivity in Lipolase mediated acylations of methyl α-d-glucopyranoside by vinyl esters of phenolic acids and their analogues

Methyl α-d-glucopyranoside as a model acceptor was acylated by several phenolic and non-phenolic vinyl esters using immobilised Lipolase. Donor specificity and regioselectivity of reaction were investigated. Conversion and rate of acylation by structurally varied donors indicates that the synthetic reactivity of Lipolase corresponds to the hydrolytic activity of feruloyl esterase type A. Lipolase exhibited remarkable regioselectivity for primary position of methyl α-d-glucopyranoside. The acylation occurred exclusively at 6-O primary position when vinyl esters of phenolic acids (hydroxybenzoates, hydroxyphenylalkanoates and hydroxycinnamates) served as acyl donors (5–77%). In addition to the major 6-O-acyl products (52–79%), 2,6-di-O-acylated derivatives were isolated from reaction mixtures (2–13%) when non-phenolic donors were used (vinyl esters of fully methoxylated derivatives of phenolic acids, along with vinyl benzoates, cinnamates or some heterocyclic analogues).     

Influence of the O-phosphorylation of serine, threonine and tyrosine in proteins on the amidic 15N chemical shielding anisotropy tensors

Density functional theory was employed to study the influence of O-phosphorylation of serine, threonine, and tyrosine on the amidic ¹⁵N chemical shielding anisotropy (CSA) tensor in the context of the complex chemical environments of protein structures. Our results indicate that the amidic ¹⁵N CSA tensor has sensitive responses to the introduction of the phosphate group and the phosphorylation-promoted rearrangement of solvent molecules and hydrogen bonding networks in the vicinity of the phosphorylated site. Yet, the calculated ¹⁵N CSA tensors in phosphorylated model peptides were in range of values experimentally observed for non-phosphorylated proteins. The extent of the phosphorylation induced changes suggests that the amidic ¹⁵N CSA tensor in phosphorylated proteins could be reasonably well approximated with averaged CSA tensor values experimentally determined for non-phosphorylated amino acids in practical NMR applications, where chemical surrounding of the phosphorylated site is not known a priori in majority of cases. Our calculations provide estimates of relative errors to be associated with the averaged CSA tensor values in interpretations of NMR data from phosphorylated proteins.