Nitrile- and Amide-converting Microbial Enzymes: Stereo-, Regio- and Chemoselectivity

Biotransformations using microbial nitrile- and amide-converting enzymes have developed considerably in the recent years. Most processes profited from the stereo-, regio- and chemoselectivity of nitrile hydratases, nitrilases and amidases specific for primary or secondary amides. The aim of this review is to discuss the developments in this branch of biotransformations in the last ca. 5 years by taking highlights from research journals, patents and industrial applications.     

Implications of pre- and post-fertilizing changes in growth and nitrogen pools following multiple applications of nitrogen fertilizer to a Pinus radiata stand over 12 years

Around the world large tracts of forest, previously available for production, have been reserved for nature conservation. This means that wood supply must be met from a reduced land base, including land of low productivity. In addition there are likely to be increasing demands on the use of managed forests for sequestering C as one means of reducing the build up of atmospheric CO2. One way for the forest industry to meet the demands of increased production would be through the use of fertilizers. Substantially increased growth from fertilizer N application has been measured in many cases while, in the northern hemisphere, atmospheric N deposition has been associated with increased growth in some forests.The possibility of using fertilizer N to increase growth, and the effect on the forest and soil, was studied in a research trial area in north-east Tasmania, Australia. Nitrogen was applied for 12 years to a 16 year old P. radiata stand in a low rainfall zone. Growth and foliar nutrient concentrations were measured to age 34 years, to determine change after attainment of steady state growth at age 25 years, and following cessation of fertilizing at age 29 years. Biomass sampling was carried out at ages 25 years, 29 years, and 34 years.Growth at the steady peak rate achieved in the fertilizer plots, of 31 m3 ha-1 periodic annual increment, was accompanied by changes in the N nutrient pools. Surface applied N built up in the surface litter layer while this layer was increasing, from 15 t ha-1 to nearly 50 t ha-1, and fertilizer was being applied between ages 25 and 29 years. Decline of total N in the soil, between ages 25 and 29 years, indicated continued uptake from that source even though fertilizer was being applied. Subsequent increases in soil N, through leaching from the litter layer, followed cessation of fertilizing.Following cessation of annual applications of N fertilizer, growth rates declined by less than 15% and remained substantially (>150%) above the control growth rates for 4 years. Over a 3 year period foliar N concentrations declined steadily, to the same as control plots, although mass of needles was not reduced 5 years after cessation of fertilizer applications and remained significantly above that of the control plots.Without fertilizers, N for new foliage must be supplied from internal recycling and from mineralization of litter and soil organic matter. There were net losses of N from the foliage and the wood, estimated at around 12 kg N ha-1 yr-1, for the fertilized trees for the 5 years following cessation of fertilizing. This indicated retention and recycling within the tree of a considerable proportion of the 104 kg N ha-1 in the foliage, at age 29 years. As rates of mineralization of soil N were likely to be low, this retention of N within the tree was important in maintaining growth rates.In the forest ecosystems investigated, with low initial content of soil organic matter and N, fertilizer N produced improved tree health and substantially increased growth, thus providing the opportunity to manage this forest for increased wood production or C sequestration. Although there was a substantial build up of N and C in the litter on the fertilized treatment, incorporation of N and C into the mineral soil was slow. Over 12 years 1.34 t N ha-1 had been applied, comparable to 40 years of atmospheric deposition at 30 kg N ha-1. There were no signs of detrimental effects from this application.     

Interacting controls on productivity in a northern Great Plains grassland and implications for response to ENSO events

In this study we investigated the causes of annual variability in peak aboveground biomass production, net ecosystem productivity (NEP) and gross ecosystem productivity (GEP) during an 8‐year period (1999–2006) in a northern Great Plains grassland near Lethbridge, Alberta, Canada. In particular, we tested for a significant relationship between growing season precipitation and productivity and determined whether soil moisture carry‐over from the previous fall–winter could alter this relationship. We also investigated the interaction between soil moisture availability and temperature in controlling grassland productivity. There was a very strong correlation between total precipitation input and average soil moisture content during the May–October growing season. However, the growing season average soil moisture contents in 2003 and 2006 were very similar to those recorded in 1999, despite lower than normal precipitation occurring in these 2 years. This resulted from a positive difference between precipitation and evapo‐transpiration that allowed significant soil moisture to be carried‐over from the previous fall–winter during both 2003 and 2006. Strong logistic relationships were observed between soil moisture and annual productivity based on data from all years except 2003 and 2006, years which had higher productivity than was predicted from the logistic regression. Interaction between temperature and soil moisture explained this difference. Productivity values in 2003 and 2006 were high compared with 1999, a year with approximately the same soil moisture content, and this resulted from the higher average growing season temperatures that were apparent in 2003 and 2006. Analysis of weather records indicated that precipitation in the month of June was significantly higher during El Niño years than during La Niña years in Lethbridge. During the study period, aboveground biomass, NEP and GEP were generally higher in El Niño years and lower in La Niña years because of associated variation in summer precipitation.     

Diatom and chrysophycean cyst profiles in sediment cores from two linked but contrasting Welsh lakes

Llyn Padarn and Llyn Peris are linked by a small river, and although originally a single larger lake, the lakes now support contrasting algal communities. A study of the sequences of diatom remains and chrysophycean cysts present in long sediment cores has been carried out to assess the historical extent of the differences in these algae between the two lakes.

Investigations have included statistical analysis to determine the precision of counting sediment samples. The most efficient sampling and counting procedure, resulting in counts of acceptable precision, involved taking a single sample of sediment from a depth horizon, preparing two replicate slides and counting the entire area of each slide. A comparison of the variation in distribution of these siliceous algae in replicate sediment samples taken from the surface sediment with the variation in distribution down the long sediment core from Llyn Padarn showed that the vertical variation greatly exceeded the horizontal variation. Thus variation in diatom numbers down the sediment core reflects changes in the alga reaching the sediments rather than horizontal patchiness of distribution in the top most layers of sediment.

Studies of the sequences of diatoms and chrysophycean cysts were carried out on a 4·75 m core from Llyn Padarn and 2·1 m core from Llyn Peris representing c. 6000 years and c. 900 years of the two lakes respective history. From c. 6000 until c. 2200 years B.P., Llyn Padarn was an acid oligotrophic lake. It appears that about 2200 years B.P., Llyn Padarn became more enriched, Asterionella formosa was the most numerous diatom preserved in the sediment at this time. Reversion to oligotrophic conditions then occurred c. 2000 years B.P. The oldest material from the Peris sediment core was characterized by centric diatoms similar to those found in Padarn sediment dating from 2000 years B.P. to the surface of the Padarn core. Thus at this time, c. 900 years B.P., the algal communities in the two lakes were similar. Both lakes were oligotrophic. However, by 200 years B.P. the chemistry of the sediment core from Peris showed evidence of extensive copper and slate mining in the environment. At this time the species of siliceous algae preserved in the Peris core changed, and the current differences in algal communities in the two lakes appear to originate from this point in history.     

Influence of the menopause and aging on spinal density in French women

Dual photon absorptiometry (DPA) was used to measure the bone mineral density (BMD) of the lumbar spine in 510 normal women from the south of France. Long-term precision was 2.2%. BMD was stable in young adults and again in women over 70 years of age. Perimenopausal women at an average age of 51 years already evidenced a slight bone diminution (5%) compared to young adults and women within 2 years of the menopause already had a 10% diminution. The average rate of apparent bone loss in this cross-sectional study was 1% per year from age 45 to 65 years, but about 75% of this decrease occurred in the first decade after the menopause. Spinal BMD in our normal French population appears to be 5–10% lower than US values.     

The occurrence and performance of leucistic Barnacle Geese Branta leucopsis

The paper reports the occurrence of whitish 'leucistic' forms in populations of Barnacle Geese Branta leucopsis. A total of 15 (including 11 in the last 21 years) have been reported in the population breeding in Svalbard and wintering in the Solway Firth, northern Britain, whereas the two other populations, though much larger, have produced only one bird of the same type between them in the last 30 years. Leucism is controlled by a single, recessive allele.
The median lifespan of leucistic birds is 2–3 years, compared to 8–10 years for normal plumaged birds. This is because they are sought out by (illegal) hunters. There is no evidence that there is any difference in pairing or breeding performance between white and normal birds, though one male, which is still alive aged 18 years, has produced 13 young; this performance is matched fay less than 2% of normal geese.
It is suggested that the Svalbard population was established recently, from a few founders from the Siberian population; if one or two of these carried the allele controlling leucism, this would explain its much higher prevalence in this population than in the other discrete groups of Barnacle Geese.     

Late Weichselian and Holocene sedimentary environments and ice rafting in Isfjorden, Spitsbergen

Multi-proxy analyses of two sediment cores from central Isfjorden were used to reconstruct the glacial history in central Spitsbergen during the Late Weichselian and the Holocene, and to relate iceberg rafting and sea-ice rafting to climatic and oceanographic changes in the north Atlantic region. A basal till was deposited beneath an ice stream prior to 12,700 cal. years BP (calendar years before the present). Several tidewater glaciers influenced the sedimentary environment during the Younger Dryas and probably already during the Allerød. The Younger Dryas cooling might be reflected by enhanced sea-ice formation and suspension settling, as well as reduced iceberg rafting. The final deglaciation was dominated by intense iceberg rafting. It terminated around 11,200 cal. years BP. Optimum Holocene climatic and oceanographic conditions with significantly reduced ice rafting occurred between c. 11,200 and 9000 cal. years BP. Ice rafting occurred almost exclusively from icebergs after 10,200 cal. years BP. The icebergs most probably originated from tidewater glaciers on east Spitsbergen, indicating the presence of a strong east–west temperature gradient at this time. An increase of iceberg rafting around 9000 cal. years BP, followed by enhanced sea-ice rafting, reflects the onset of a general cooling in the western Barents Sea–Svalbard region. Comparatively intense rafting from icebergs and sea ice between 9000 and 4000 cal. years BP is related to this cooling. A general reduction in ice rafting after 4000 cal. years BP is most probably the result of the enhanced formation of shore-fast and/or more permanent sea-ice cover, reducing the drift of icebergs and sea ice in the fjord. The results indicate that the palaeoenvironmental conditions on central Spitsbergen to a large degree depended on the oceanographic conditions in the western Barents Sea and west off Spitsbergen. However, climatic trends affecting Greenland and the entire north Atlantic region can also be identified.     

Extraction of osteocalcin from fossil bones and teeth

Osteocalcin (also called 'bone Gla-protein') was detected in fossil bovid bones ranging from 12,000 years to 13 million years old and in rodent teeth 30 million years old. Both the antigenic activity and the protein-bound Gla-residues have remained intact. The protein is indistinguishable from recent bovine osteocalcin when analyzed by HPLC using ion exchange and size exclusion columns. If sufficient amounts can be extracted and an adequate purification procedure is established, this would be the first time that amino acid sequences in a protein from fossil bones may be determined. Such sequence data could offer a new approach to the phylogenetic study of extinct taxa.     

Work-Related and Non-Work-Related Injury Deaths in the U.S.: A Comparative Study

This study assesses the percentage of traumatic fatalities attributable to work-related causes in the US, by cause of death and population demographics. The 1993-1998 Vital Statistics Mortality data from the National Center for Health Statistics were used. There were 848,945 traumatic fatalities (E800-E999) among the general population 16 years or older in the US during this time; of these, 32,044 were work-related accounting for 3.8% of all the fatalities. The work-related percentage varied from 62.7% for machine-related deaths to 0.7% for suicides, from 4.9% for males to 1.0% for females, from 9.8% in Alaska to 1.5% in Arizona, from 4.2% for decedents with 1 to 4 year college educations to 2.9% for decedents with high school or less, from 4.4% for races other than white and black to 2.6% for black. Mean age-at-death was 42 years for work-related vs. 48 years for non-work-related fatalities. This difference is more pronounced for deaths from falls (45 years vs. 78 years). Conversely, victims of work-related homicide were older than non-work-related (41 years vs. 33 years). A more complete understanding of the burden of traumatic fatalities attributable to work-related causes requires consideration of the total work-related percentage, causes of death, and population demographics.     

Frequency and distribution of enamel hypoplasias in a historic skeletal sample

A skeletal sample of 296 individuals from a 19th century American poorhouse cemetery is examined for the frequency and chronological distribution of linear enamel hypoplasias on the mandibular canines and maxillary central incisors. Dental enamel hypoplasias may be considered to be indicators of increased exposure to health risk at the time of weaning. The purpose of this study is to examine childhood stress and provide a relative measure of that stress, as evidenced by hypoplasias, in a historic sample that represents an industrializing population. The frequency of enamel hypoplasias per individual by tooth ranged from 70 to 73%, with a peak age at stress of 2.5 to 3 years for the maxillary central incisor and 3.5 to 4 years for the mandibular canine. There were no significant differences in the presence of hypoplasias between males and females. The peak age at stress between 2.5 and 4 years in this 19th century sample transects the ranges reported for prehistoric populations (2-6 years) and for modern groups (0-3 years). These results indicate that the stress associated with weaning probably occurred earlier in incipient industrial societies than in prehistoric hunter/gatherers and agriculturalists, yet not as early as in modern industrial groups. The high level of childhood stress in this skeletal sample compared with that of other samples may indicate a change in health, at least among the lowest class, associated with the cultural transition from an agricultural to an industrial society.     

The Influence of Physical Habitat,Pyrethroids, and Metals on Benthic Community Condition in an Urban and Residential Stream in California

This study was designed to characterize benthic communities and physical habitat in both an urban (Kirker Creek) and residential (Pleasant Grove Creek) stream in California in late spring of 2006 and 2007. Concurrent water quality evaluations, physical sediment parameters, pyrethroids, bulk metals, and SEM/AVS ratios were also measured during both years of this study. The relationship of various benthic metrics to physical habitat metrics, pyrethroids, and metals was evaluated for each stream using stepwise multiple linear regressions with both years combined for each stream, as well as both years and both streams combined, to increase the statistical power for determining significant relationships. Physical habitat was determined to be poor in each stream during both years of sampling. More than 100 benthic taxa were reported annually for both streams based on 2006 and 2007 sampling. A significant result from the stepwise regression analysis combining data for 2 years across both streams is that when habitat metrics and to a lesser degree metals are considered in the statistical models pyrethroids do not display any significant relationships to the benthic metrics. In summary, it is apparent from this analysis that the health of benthic communities in both streams is primarily affected by habitat metrics.     

Effect of current and midlife obesity status on mortality risk in the elderly

The primary purpose of this study was to determine whether current and midlife obesity status provide independent information on mortality risk in elderly persons. Analyses were based on 3,238 participants from the original Framingham Heart Study (FHS) cohort who lived to at least 70 years of age and who had BMI measures from when they were in their 50s. Within this group of 70-year olds, obesity based on current BMI was associated with a 21% increased risk of mortality (P = 0.019) whereas obesity in 70-year olds based on BMI measures obtained at around 50 years of age was associated with a 55% increased risk of mortality (P < 0.0001). Compared to 70-year olds who were nonobese at both 50 and 70 years of age, mortality risk was increased by 47% (P < 0.001) in those who were obese at both 50 and 70 years of age, increased by 56% (P < 0.001) in those who were obese at 50 years of age and nonobese at 70 years of age, and not significantly different (P > 0.9) in those who were nonobese at 50 years of age and obese at 70 years of age. In summary, in this cohort of elderly adults, midlife and current BMI had independent effects on mortality risk. Specifically, although mortality risk was increased in obese older adults who were already obese at midlife, this was not the case for newly obese older adults. Conversely, nonobese older adults who were obese at midlife had an increased mortality risk. These observations imply that it is imperative to consider an elderly adult's BMI in context of their BMI at midlife.     

Abundance and Vertical Distribution of Longidorus breviannulatus Associated with Corn and Potato

Longidorus breviannulatus was detected in a field planted to corn after 13 years of potato. Nematode populations were maintained in this field in adjacent corn and potato plots for 2 years but did not increase significantly on either crop. Population levels increased until approximately 60 days after planting and then declined until the end of the growing season. Overwinter mortality was negligible. The vertical distribution of the nematode population changed during the course of the season. More nematodes were recovered from depths of 0-15 cm in early season samples and from depths of 15-30 cm in late season samples. Data indicated that this redistribution was due to nematode migration.     

Cortisol secretion in the elderly. Influence of age,sex and cardiovascular disease in a Chinese population

Adrenal function and aging have been the object of intense interest in recent years. In this study we analyzed morning (08:00 h) serum cortisol concentrations from a sample of Chinese subjects aged from 31 to 110 years. These levels differed according to age, health status and sex, although the sex difference was confirmed only among the healthy elderly. These results suggest that age (older than 60 years), disease and male sex are associated with increased morning serum cortisol levels in a Chinese population.     

Age-specific birth rate and lifetime reproductive success of chimpanzees at Bossou,Guinea

Preliminary calculations of the age-specific birth rate for wild female chimpanzees were based on demographic records from a long-term study at Bossou, Republic of Guinea. Primiparous age was 12-14 years. Birth rate for a female reached a peak of 0.333 a year at 20-23 years, and then decreased until menopause at more than 40 years of age. Mean birth rate for a female of more than 12 years was 0.197 a year. Mean interbirth interval was 4.6 years overall, but 5.1 years, if all cases in which the previous infant had died within its first three years were excluded. Infant survival rate for the first four years was 0.727 and that of juveniles (four to seven years) was 0.714; however, that of adolescents (eight to 11 years) was only 0.222. Some adolescents who disappeared from Bossou are thought to have migrated to adjacent habitats. From age-specific birth rate and survival rate, the lifetime reproductive success was calculated as only 0.74 offspring per female. This rose to 2.39 when adolescent survival rate was assumed to be the same as that of juveniles. This must be less than the minimum reproductive success required for continued survival of the population. The recent and continuing degradation of the environment will lead to the extermination of this species from the area in the near future. © 1994 Wiley-Liss, Inc.     

Vertical growth of the anterior face and cranium in inner city Negro children

A longitudinal cephalometric study was conducted on the vertical growth of the cranium and anterior face on 60 inner city American Negro children, an equal number of boys and girls from four to nine years. Three vertical measurements were used for the purpose of this study. The head height was measured from sellion to bregma, bony nasal height from nasion to anterior nasal spine, and lower facial height from anterior nasal spine and lower facial height from anterior nasal spine to menton. The data were analyzed at annual ages and observations made relative to the growth trends. The findings of this study were compared with those on Caucasian children. No significant statistical difference was found in the mean head (cranial vault) height between the Negro and Caucasian children. The mean bony nasal height expressed as a percentage of subnasal height was found to be less in the Negro children. The difference decreased with age. The annual increment of growth in head height was greater from four to seven years than from seven to nine years. The findings are considered to imply that severe malnutrition may influence child growth.     

Amplification of mitochondrial DNA fragments from ancient human teeth and bones

We extracted and visualized DNA from ancient human teeth and bones of 150 to 5,500 years B.P. from three deposits from the south of France. The DNA extracted was used as template for PCR with specific primers corresponding to a portion of the human mitochondrial genome. In our samples, we have amplified a specific DNA fragment of 121 bp which, in the case of one bone of 150 years B.P. has been cloned and sequenced. We show that this sequence is identical to the homologous region of human mitochondrial DNA. The striking implications of this new method for archaeological and paleontological studies are exposed.     

G Protein-Coupled Receptors in and on the Cell Nucleus: A New Signaling Paradigm?

Signaling from internalizing and endosomal receptors has almost become a classic GPCR paradigm in the last several years. However, it has become clear in recent years that GPCRs also elicit signals when resident at other subcellular sites including the endoplasmic reticulum, Golgi apparatus, and the nucleus. In this review we discuss the nature, function, and trafficking of nuclear GPCR signaling complexes, as well as potential sources of endogenous and exogenous ligands. Finally, we pose a series of questions that will need to be answered in the coming years to confirm and extend this as a new paradigm for GPCR signaling.     

Recent divergences and size decreases of eastern gorilla populations

Compared with other African apes, eastern gorillas (Gorilla beringei) have been little studied genetically. We used analysis of autosomal DNA genotypes obtained from non-invasively collected faecal samples to estimate the evolutionary histories of the two extant mountain gorilla populations and the closely related eastern lowland gorillas. Our results suggest that eastern lowland gorillas and mountain gorillas split beginning some 10 000 years ago, followed 5000 years ago by the split of the two mountain gorilla populations of Bwindi Impenetrable National Park and the Virungas Massif. All three populations have decreased in effective population size, with particularly substantial 10-fold decreases for the mountain gorillas. These dynamics probably reflect responses to habitat changes resulting from climate fluctuations over the past 20 000 years as well as increasing human influence in this densely populated region in the last several thousand years.     

Stable carbon and nitrogen isotope values of bone and teeth reflect weaning age at the Medieval Wharram Percy site,Yorkshire, UK

We report on the measurements of carbon and nitrogen stable isotopes of both bone and teeth from a single site and population (Medieval Wharram Percy), undertaken to explore variations due to weaning in a past population. There have been a number of recent studies of weaning using delta(15)N values of ribs, and we indicate a number of assumptions that must be met before the results of such studies can be correctly interpreted. We found that rib collagen delta(15)N values decrease to adult levels after age 2 years, indicating that weaning occurred at or before this age. Rib collagen delta(13)C values are also more enriched than adult delta(13)C values before age 2 years, and we argue that this is due to the so-called "carnivore" effect in delta(13)C. We measured teeth and rib delta(15)N values from the same individuals and found that for individuals up to age 11 years, tooth dentine delta(15)N is higher than adult rib delta(15)N values, indicating that the dentine was formed during breast-feeding and that there was almost no turnover of dentine since. We observed some decrease in delta(13)C and delta(15)N rib values, compared to adult rib and teeth values, for the few years after weaning that may relate to a theoretically predicted physiological nitrogen imbalance during this period of rapid growth, but this is more likely due to a childhood diet (up to age 9) which was isotopically different from later diet, possibly consisting of a greater proportion of plant foods.