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PubMed1975

Transfer of the methyl group of methionine to choline and to tRNA in the honeybee Apis mellifica L.

Contrary to some previous reports on the absence of biological transmethylation reactions in some insect species, the transfer of the methyl group of methionine-methyl 14C leading to choline and to methylated bases in tRNA was shown in the honeybee Apis mellifica. The addition of antibiotics to the food of the insect does not diminish the incorporation of radioactivity, proving that intestinal bacteria are not responsible for the methylation reactions observed.

Animals↗
PubMed1991

Learning by honeybees (Apis mellifera) on arrival at and departure from a feeding place.

The question of when in the course of a visit to a feeding place foraging honeybees (Apis mellifera) learn about its location was studied in Experiment 1 by moving the animals a short distance after they arrived and began to feed. A preference for the arrival place developed, although less rapidly than in control animals for which the arrival and departure places were the same. In Experiments 2-5, a distinctive object was used to define the location of the feeding place. When the object was removed after arrival or introduced only after arrival, the animals learned less about its color and shape than did control animals for which it was present throughout each visit. The results contradict the claim that honeybees learn about certain characteristics of a feeding place only on arrival and about others only on departure.

Animals↗
PubMed1992

Learning in honeybees (Apis mellifera) as a function of sucrose concentration.

Foraging honeybees (Apis mellifera) were trained with 2 successively presented targets differing in color or odor, one of which always contained a 5-microliters drop of 50% sucrose solution and the other, a 5-microliters drop of 20% sucrose solution. Latency of response to each target was measured during the training, and at the conclusion, preference was measured in an unrewarded choice test. Analysis of the latencies showed both a prospective effect (faster response to the 50% target than to the 20% target) and a nonassociative retrospective effect (faster response after leaving the 20% target than after leaving the 50% target) reminiscent of the frustration effect in rats. The results both for prospective latency and for choice can be understood on the simple theory that the attractiveness of a target depends on the strength of its association with sucrose and that the effect of concentration is on asymptotic strength.

Animals↗
PubMed1992

Simultaneous conditioning in honeybees (Apis mellifera).

Honeybees (Apis mellifera) were classically conditioned with odor as conditioned stimulus (CS), sucrose as unconditioned stimulus (US), and proboscis extension as response. The purpose of Experiment 1 (Ns = 26 and 27) was to look for facilitation of forward conditioning by CS-US overlap, but rapid conditioning without overlap left little room for improvement. In 2 further experiments, CS and US were simultaneous, and response to odor alone was measured in subsequent tests. In Experiment 2, a Simultaneous group (N = 25) responded more to the training odor than did an Unpaired control group (N = 25). In Experiment 3, a differentially conditioned Simultaneous group (N = 29) responded more to an odor paired with sucrose in training (S+) than to an odor presented alone (S-). The implications of the results for the problem of the role of amount of reward in honeybee learning are considered.

Animals↗
PubMed1992

The antigenicity of the carbohydrate moiety of an insect glycoprotein, honey-bee (Apis mellifera) venom phospholipase A2. The role of alpha 1,3-fucosylation of the asparagine-bound N-acetylglucosamine.

A rabbit polyclonal antiserum raised against honey-bee (Apis mellifera) venom phospholipase A2 (PLA2) contains antibodies that react exclusively with its glycosylated variants and cross-react with plant glycoproteins. The interaction of anti-(horseradish peroxidase) antiserum with PLA2 suggests the existence of a carbohydrate determinant common to both glycoproteins. E.l.i.s.a. binding and inhibition experiments, employing glycoproteins and glycopeptides of plant and animal origin with known N-glycan structures, in combination with chemical and enzymic deglycosylation, identified alpha 1,3-fucosylation of the asparagine-bound N-acetylglucosamine as the antigenic determinant. This fucose residue is present in the N-glycan of PLA2 and is frequently found in plant glycoproteins, whereas mammalian glycoproteins lack this modification.

Acetylglucosamine↗
PubMed1977

Estimation of the number of sex alleles and queen matings from diploid male frequencies in a population of Apis mellifera.

The distribution of diploid males in a population of Apis mellifera was obtained by direct examination of the sexual phenotypes of the larvae. Using these data, estimates are derived for the number of sex alleles and the number or matings undergone by the queen. The number of sex alleles is estimated to be 18.9. The estimate is larger than previous ones, which have ranged between 10 and 12. However, the increase in the number of sex alleles can be explained by the large effective population number for our data. The best estimator of the number of matings by a queen is a maximum likelihood type that assumes a prior distribution on the number of matings. For the data presented here, this estimate is 17.3. This estimate is compared to others in the literature obtained by different approaches.

Alleles↗
PubMedDate not supplied

Geographical overlap of two mitochondrial genomes in Spanish honeybees (Apis mellifera iberica).

Restriction enzyme cleavage maps of mitochondrial DNA from the Spanish honeybee, Apis mellifera iberica (Hymenoptera: Apidae), were compared with those from the European subspecies A. m. mellifera, A. m. ligustica, and A. m. carnica, and the African subspecies A. m. intermissa and A. m. scutellata. The mitochondrial DNA (mtDNA) of the two African subspecies can be distinguished by restriction fragment polymorphisms revealed by Hinf I digests. Two distinct mtDNA types were found among Spanish honeybees: a west European mellifera-like type, which predominates in the north of Spain, and an African intermissa-like type, which predominates in the south. Spain appears to be a region of contact and hybridization between the two subspecies A. m. intermissa and A. m. mellifera, which respectively represent African and west European honeybee lineages. This natural boundary between European and African honeybee populations in the Old World may provide a model for predicting the eventual outcome of the colonization of North America by introduced African honeybees.

Africa↗
PubMed1991

Differential response of Apis mellifera acetylcholinesterase towards pirimicarb.

The kinetic analysis of Apis mellifera acetylcholinesterase inhibition by the carbamate pirimicarb showed that native and detergent-solubilized membrane enzyme exhibited slightly different carbamylation kinetics. The acetylcholinesterase form sensitive to phosphatidylinositol-specific phospholipase C (PI-PLC) was carbamylated more rapidly (kapp = 36.4 X 10(-3) min-1) than the PI-PLC-resistant counterpart (kapp = 10.13 X 10(-3) min-1) which had a behavior close to that of the soluble tryptic enzyme (kapp = 11.89 X 10(-3) min-1). A difference in acetylcholinesterase sensitivity towards pirimicarb was also observed between foraging and emerging bees. These results show that the molecular structure, the mode of preparation and the source of acetylcholinesterase from the bee head should be taken into account in accurate toxicological studies.

Acetylcholinesterase↗
PubMed1977

Biochemical typing of urinary Escherichia coli strains by means of the API 20 E enterobacteriaceae system.

With the API 20 E Enterobacteriaceae system of biochemical testing, a biotype, coded numerically, was determined for each of 574 strains of Escherichia coli isolated from patients with urinary tract infection. The serotypes of the strains were also determined. Fifty-five different biotypes were identified, two accounting together for 42% of the strains examined and seven others each accounting for between 8.4 and 1.9%. There was little correlation between biotype and serotype. Fifty pairs of strains were isolated from patients before treatment. In 43 the biotype and serotype of both strains of each pair were the same. In six pairs the biotype, but not the serotypes, differed, the difference being limited to the results of the tests for lysine decarboxylase. The biotypes of the strains of the remaining pair differed widely although their serotypes were the same. It is suggested that this method of biotyping offers a simple but accurate way of discriminating between recrudescent urinary tract infection caused by E. coli and that due to reinfection.

Bacteriuria↗
PubMed1992

Evolutionary history of the honey bee Apis mellifera inferred from mitochondrial DNA analysis.

Variability of mitochondrial DNA (mtDNA) of the honey bee Apis mellifera L. has been investigated by restriction and sequence analyses on a sample of 68 colonies from ten different subspecies. The 19 mtDNA types detected are clustered in three major phylogenetic lineages. These clades correspond well to three groups of populations with distinct geographical distributions: branch A for African subspecies (intermissa, monticola, scutellata, andansonii and capensis), branch C for North Mediterranean subspecies (caucasica, carnica and ligustica) and branch M for the West European populations (mellifera subspecies). These results partially confirm previous hypotheses based on morphometrical and allozymic studies, the main difference concerning North African populations, now assigned to branch A instead of branch M. The pattern of spatial structuring suggests the Middle East as the centre of dispersion of the species, in accordance with the geographic areas of the other species of the same genus. Based on a conservative 2% divergence rate per Myr, the separation of the three branches has been dated at about 1 Myr BP.

Animals↗
PubMed1991

GDP-fucose: beta-N-acetylglucosamine (Fuc to (Fuc alpha 1----6GlcNAc)-Asn-peptide)alpha 1----3-fucosyltransferase activity in honeybee (Apis mellifica) venom glands. The difucosylation of asparagine-bound N-acetylglucosamine.

Incubation of honeybee (Apis mellifica) venom-gland extracts with GDP-[14C]fucose and GlcNAc beta 1----2Man alpha 1----6(GlcNAc beta 1----2Man alpha 1----3)Man beta 1----4GlcNAc beta 1----4(Fuc alpha 1----6)GlcNAc beta 1----N-Asn-peptide(NAc) gave a labeled product in 40% yield. Analysis by 500-MHz 1H-NMR spectroscopy indicated the transferred fucose-(Fuc) residue to be alpha 1----3-linked to the Asn-bound GlcNAc. Further proof was provided by one-dimensional and two-dimensional 1H-NMR analysis of the incubation mixture, after incubation with beta-N-acetylhexosaminidase. The established carbohydrate structure (formula; see text) proves the existence of a novel alpha 1----3-fucosyltransferase with the ability to effect difucosylation of the Asn-bound GlcNAc in N-glycans.

Acetylglucosamine↗
PubMed1992

Use of the API rapid NFT system for identifying nonfermentative and fermentative marine bacteria.

Thirty-five American Type Culture Collection type strains of marine bacteria were used to evaluate the Rapid NFT system (API Analab Products, Plainview, N.Y.) for use in identifying heterotrophic marine bacteria. The 21 biochemical and assimilation tests on the Rapid NFT test strips were treated according to the manufacturer's protocol, which included use of AUX medium (provided with the Rapid NFT system) for preparing assimilation tests, and by substituting phenol red broth base (BBL Microbiology Systems, Cockeysville, Md.) with and without an oil overlay for the AUX medium. A seven-digit numerical profile was obtained for each NFT test strip from each of the three procedures and matched to its corresponding number in the Rapid NFT identification codebook. Also, all biochemical and assimilation test results were analyzed with SASTAXAN and SAS/GRAPH programs (SAS Institute, Inc., Cary, N.C.); similarity matrices were computed for all 35 strains. For comparison purposes, bacterial strains were grouped at a similarity level of 70%. The results indicated a low efficacy of identification for all three procedures. In addition, similarity matrix analysis showed more cohesive grouping based on results of phenol red broth base-treated strains than for the AUX medium provided by the manufacturer. However, none of the three treatments provided exclusive grouping of type strains at the genus level. Thus, the reliability of the data obtained from the NFT system and modifications thereof should be evaluated carefully when environmental isolates are characterized.

Bacteria↗
PubMed1992

API Listeria, a new and promising one-day system to identify Listeria isolates.

API Listeria is a new 10-test strip for 24-h biochemical identification of Listeria isolates. With this commercial system, 85% of 646 Listeria strains, including atypical isolates selected for this study, were recognized at the species and subspecies level without a complementary test. A new test differentiates Listeria monocytogenes from L. innocua on the basis of the absence of arylamidase from the former. With this system, 97.7% (252 of 258) of the L. monocytogenes strains tested were correctly identified and differentiated from 99.4% (175 of 176) of the L. innocua strains also tested. Gram-positive bacteria other than Listeria spp. gave quite different biochemical patterns. This system considerably reduced the time needed for conventional identification, since results were available within 18 to 24 h.

Bacteriological Techniques↗
PubMed1979

Rapid identification of Enterobacteriaceae with the micro-ID system versus API 20E and conventional media.

The Micro-ID system for rapid (4 h) identification of Enterobacteriaceae was evaluated by testing 433 enteric bacilli and 9 other gram-negative bacilli. Each isolate was identified with conventional tubed media and was also tested in the Micro-ID and API 20E systems. The overall accuracy of both systems was 97%. Micro-ID tests for the Voges-Proskauer reaction, indole and H2S production, and ornithine and lysine decarboxylase all demonstrated a 97 to 99% correlation with conventional methods. Only 86% of the Micro-ID urease tests agreed with Christenson urea agar. Two inoculum densities were tested in Micro-ID panels, with 157 stock cultures. Over 90% of the tests were unaffected by changes in inoculum density. Tests with four control strains suggested that the Micro-ID system was more reproducible when a light inoculum was used. The Micro-ID system was found to be a very convenient method for rapid, accurate, and precise identification of the Enterobacteriaceae.

Bacteriological Techniques↗
PubMed1979

Rapid identification of Prototheca species by the API 20C system.

The conventional auxanographic method of testing for the assimilation of carbohydrates and alcohols by the various species of Prototheca requires at least 2 weeks of incubation at 25 to 30 degrees C before definitive results are obtained. Even though Prototheca spp., in culture as well as in fixed tissues, can be identified more rapidly by fluorescent-antibody techniques in which species-specific reagents are used, such diagnostic facilities and reagents are not available in most diagnostic laboratories. The API 20C clinical yeast identification system, a commercially available ready-to-use micromethod, was found to permit the definitive identification of P. stagnora, P. wickerhamii, and P. zopfii within 4 days.

Carbohydrate Metabolism↗
PubMed1976

Inoculation of API-20E from positive blood cultures.

The API-20E system (Analytab Products, Inc., Plainview, N. Y.) was inoculated from 4- to 6-h tryptic soy broth cultures that had been inoculated from positive blood cultures containing gram-negative bacilli. This method gave the same genus and species identification for 139 of 140 organisms (47 patient and 96 simulated positive cultures) when compared to the Analytab Products, Inc., recommended method of inoculation.

Bacterial Infections↗
PubMed1978

Standardization of the Analytab Enteric (API 20E) system to increase accuracy and reproducibility of the test for biotype characterization of bacteria.

Procedures employing the Analytab Enteric (API 20E) system were standardized to improve the accuracy and reproducibility of the individual biochemical tests so that the system could be used to biochemically characterize bacteria for epidemiological studies. The standardized method and the method recommended by the manufacturer (routine method) were tested in parallel with 130 clinical isolates. Tests with 100 randomly selected clinical isolates demonstrated that the standardized method was more accurate and reproducible than the routine method. In addition, the standardized method accurately identified 24 of 30 clinical isolates which could not be identified with the routine method.

Bacteriological Techniques↗