Three unique base pair changes in a family with Gaucher disease

Summary Single-stranded cDNA was prepared from RNA obtained from a patient with type 1 Gaucher disease. The cDNA was amplified in vitro and analyzed by sequencing. Three base-pair changes were identified which included a G to C transversion at nucleotide 3119 of the active gene (Asp¹⁴⁰His), an A to C transversion at nucleotide 3170 (Lys¹⁵⁷Gln) and a G to A change at nucleotide 5309 (Glu³²⁶Lys). To study the mode of inheritance of the three different base-pair changes, genomic DNA was prepared from blood or skin fibroblasts of several family members. Genomic glucocerebrosidase DNA sequences were amplified and subjected to hybridization with allele-specific oligonucleotides (ASOs). The hybridization profiles demonstrated that two of the basepair changes originated from the mother and were transmitted to her two affected sons and to a grandchild, while the third base-pair change, originating from the father, was transmitted to his two affected sons, a carrier daughter and a second grandchild. Tests of other patients with Gaucher disease failed to disclose the presence of the three base-changes. This is a unique family with three base-pair changes tightly linked to Gaucher disease.     

Isolation and properties of the soluble c-type cytochromes of the dinoflagellate Peridinium cinctum

Four soluble cytochromes of the c type were isolated from the freshwater dinoflagellate Peridinium cinctum collected from Lake Kinneret, Israel. Cytochrome c with alpha-band maximum at 550 nm in the reduced state had a molecular mass of 10,200 Da, pI 7.4, and Em of 278 m V. This cytochrome was active in the respiratory chain of beef heart Keilin-Hartree particles. Cytochrome c-553 had a molecular mass of 13,200 Da, pI 4.9, and Em of 384 m V, and was active in light induced electron transport of Euglena gracilis chloroplast fragments. Cytochrome c-554 had a molecular mass of 13,500 Da, pI 4.4, and Em of 326 m V. This cytochrome was inactive in light induced electron transport but competed with cytochrome c-552 of Euglena in the assay. The acidic cytochrome c-557 was present in very small quantities. The properties of the soluble c-type cytochromes of P. cinctum are compatible with the classification of dinoflagellates as primitive eucaryotes.     

Longevity of hibernating queens in Vespa orientalis (Hymenoptera: Vespinae)—Effects of physical and chemical treatments

Young queens of V. orientalis collected from nests in the field at the end of the season, just before the hornets naturally enter hibernation, were evaluated for longevity under varying laboratory conditions. Queens kept under full illumination and heating had a briefer life span than did queens kept under full illumination alone or under complete heating alone. All, however, were shorter lived than control queens kept under the thermal and photoperiodic conditions prevailing at that time in nature. Feeding of theophylline to the queens caused them to emerge from hibernation and succumb to an early death. Feeding of allopurinol to the queens diminished their activities relative to control queens but did not abbreviate their life span compared to the control queens.     

Hydration of 3-cyanopyridine to nicotinamide by crude extract nitrile hydratase

Summary The kinetic and stability characteristics of crude extract nitrile hydratase fromBrevibacterium R-312 were studied for the hydration of 3-cyanopyridine to nicotinamide. The enzyme was substrate and product inhibited and had the following kinetic constants:K _m =28 mM;K _p =36 mM;K _s =155 mM;V _m =5.8 mol/min/mg protein (25°C). Itsmaximum temperature and pH (phosphate buffer) were 35°C and 8.0, respectively and it had half-lives of 50 days, 10 days and 1 day at 4°C, 10°C and 25°C, respectively. The crude extract also exhibited amidase activity on nicotinamide, but it became significant only at nicotinamide concentrations greater than 300 mM. Mathematical models for batch and fed-batch hydrations were developed to account for substrate and product inhibitions and for enzyme decay. They predicted to within 10% experimental results for initial substrate and final product concentrations up to 300 mM; the accuracies decreased at higher concentrations primarily because of the relatively rapid hydrolysis of nicotinamide.     

Detection of aflatoxigenic molds in grains by PCR.

Aflatoxins are carcinogenic metabolites produced by several members of the Aspergillus flavus group in grains and floods. Three genes, ver-1, omt-1, and apa-2, coding for key enzymes and a regulatory factor in aflatoxin biosynthesis, respectively, have been identified, and their DNA sequences have been published. In the present study, three primer pairs, each complementing the coding portion of one of the genes, were generated. DNA extracted from mycelia of five Aspergillus species, four Penicillium species, and two Fusarium species was used as PCR template for each of the primer pairs. DNA extracted from peanut, corn, and three insect species commonly found in stored grains was also tested. Positive results (DNA amplification) were achieved only with DNA of the aflatoxigenic molds Aspergillus parasiticus and A. flavus in all three primer pairs. The detection limit of the PCR was determined by using the primer pairs complementing the omt-1 and ver-1 genes. Sterile corn flour was inoculated separately with six different molds, each at several spore concentrations. Positive results were obtained only after a 24-h incubation in enriched media, with extracts of corn inoculated with A. parasiticus or A. flavus, even at the lowest spore concentration applied (10(2) spores per g). No DNA spores per g). It is concluded that genes involved in the aflatoxin biosynthetic pathway may form the basis for an accurate, sensitive, and specific detection system, using PCR, for aflatoxigenic strains in grains and foods.     

Prevalence of nine mutations among Jewish and non-Jewish Gaucher disease patients.

The frequency of nine different mutated alleles known to occur in the glucocerebrosidase gene was determined in 247 Gaucher patients, of whom 176 were of Jewish extraction, 2 were Jewish with one converted parent, and 69 were of non-Jewish origin. DNA was prepared from peripheral blood, active glucocerebrosidase sequences were amplified by using the PCR technique, and the mutations were identified by using the allele-specific oligonucleotide hybridization method. The N37OS mutation appeared in 69.77% of the mutated alleles in Jewish patients and in 22.86% of the mutated alleles in non-Jews. The 84GG mutation, which has not been found so far among non-Jewish patients, existed in 10.17% of the disease alleles among Jewish patients. The IVS + 1 mutation constituted 2.26% of the disease alleles among Jewish patients and 1.43% among the non-Jewish patients. RecTL, a complex allele containing four single-base-pair changes, occurred in 2.26% of the alleles in Jewish patients and was found in two (1.43%) of the patients of non-Jewish extraction. Another complex allele, designated "RecNciI" and containing three single-point mutations, appeared in 7.8% of alleles of non-Jewish patients and in only two (0.56%) of the Jewish families. The prevalence of the L444P mutation among non-Jewish Gaucher patients was 31.43%, while its prevalence among Jewish patients was only 4.24%. The prevalence of two other point mutations--D409H and R463C--was 5.00% and 3.57%, respectively, among non-Jewish patients and was not found among the Jewish Gaucher patient population. The prevalence of the R496H mutation, found so far only among Jewish patients, was 1.13%. The results presented demonstrate that seven mutations identify 90.40% of the mutations among Jewish patients and that these seven mutations allow diagnosis of only 73.52% of the non-Jewish patients. Identification of additional mutant alleles will enhance the accuracy of carrier detection.     

Credit or debit? Resource input changes population dynamics of city-slicker birds

The underlying evolutionary mechanisms of urban bird populations have hardly been studied. High food density and low predation risk serve to explain the global pattern of extremely high urban bird population densities. Both these bottom-up and top-down effects are paradoxical since the per capita amount of food is small due to competition, and domestic predator density is high in cities. The bottom-up paradox can be resolved by taking into account the high food resource-predictability in cities. Concerning the top-down effect, recent studies suggest that at least when it comes to nest predation the effect of cats is minor. I suggest that the combination of high food predictability and low predation risk in cities alter bird foraging behaviour, which in turn affects population dynamics. In terms of density, the result is that bird populations exceed the carrying capacity of the urban environment, costing heavily on body condition and/or life span. Under such conditions the population should consist of a few winners and many losers. Only the winners have sufficient access to food resources and the opportunity to reproduce. The highly predictable continuous input of food in the urban environment allows them to "live on their credit". They may trade off between offspring body condition and clutch size. In the lack of predation, the losers among the fledglings may survive for a relatively long period, getting just enough energy to survive. Though they may never become healthy enough to reproduce, they will have a major contribution to the observed population density. Results of several case studies seem to support the credit card hypothesis and suggest that it can serve as a general rule for the evolution of animal populations and communities in highly predictable human managed environments.