Isolation and sequence of the gene encoding ornithine decarboxylase, SPE1, from Candida albicans by complementation of a spe1 delta strain of Saccharomyces cerevisiae

The gene encoding ornithine decarboxylase, SPE1, from the pathogenic yeast Candida albicans has been isolated by complementation of an ornithine decarboxylase-negative (spe1 delta) strain of Saccharomyces cerevisiae. Four transformants, three of which contain plasmids with the SPE1 gene, were isolated by selection on polyamine-free medium. The C. albicans ornithine decarboxylase (ODC) showed high homology with other eukaryotic ODCs at both the amino acid and nucleic acid levels.     

McNemar replies.

Concedes that A. B. Silverstein's (see PA, Vol 54:Issue 4) correction to the present author's formula (see record 1974-24264-001) was not based on fallacious reasoning but on an unclear rationale. The present author concludes, tentatively, that for WAIS and WISC situations, the selection of a low-reliability test instead of an equally good test with higher reliability will lead to trivially different correlations with total scores. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

More on the Wilson Test.

Sheffield (see 33: 132) has presented a conceptually and computationally simplified adaptation of a distribution-free test for analysis of variance hypothesis. The author presents a logical analysis of the technique demonstrating it to be basically unsound. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Statistics can mislead.

Discusses serious statistical problems in S. Scarr and R. A. Weinberg's (see record 1977-07996-001) article on 130 Black children adopted by Whites, in which the authors attempted to ascertain the relative contributions of 10 social and 2 biological variables to IQ variance. Corrected statistical analyses show opposing trends for the contributions of nurture and nature. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Isolation of a gene encoding a putative polyamine transporter from Candida albicans, GPT1

A gene encoding a transport protein from the pathogenic yeast, Candida albicans, has been isolated during a complementation experiment utilizing an ornithine decarboxylase-negative (spe1 Delta) strain of Saccharomyces cerevisiae. This gene restores gamma-aminobutyric acid (GABA) transport to a GABA transport-negative mutant of S. cerevisiae and encodes a protein which putatively allows transport of one or more of the polyamines. We have assigned the name GPT1 (GABA/polyamine transporter) to this gene.     

Serine protease of hepatitis C virus expressed in insect cells as the NS3/4A complex

Hepatitis C virus (HCV) protease NS3 and its protein activator NS4A participate in the processing of the viral polyprotein into its constituent nonstructural proteins. The NS3/4A complex is thus an attractive target for antiviral therapy against HCV. We expressed the full-length NS3 and NS4A in insect cells as a soluble fusion protein with an N-terminal polyhistidine tag and purified the two proteins to homogeneity. Cleavage at the junction between HisNS3 and NS4A occurs during expression, producing a noncovalent complex between HisNS3 and NS4A with a subnanomolar dissociation constant. We purified the HisNS3/4A complex by detergent extraction of cell lysate and by metal chelate chromatography. We removed the His tag by thrombin cleavage and then further purified the complex by gel filtration. The purified NS3/4A complex is active in a protease assay using a synthetic peptide substrate derived from the NS5A-NS5B junction, with kcat/K(m) of 3700 (+/- 600) M-1 s-1, an order of magnitude above those previously reported for NS3 expressed by other strategies. This high protease activity implies that the full-length sequences of NS3 and NS4A are required for optimal activity of the NS3 protease domain. We examined the dependence of the NS3/4A protease activity on buffer conditions, temperature, and the presence of detergents. We find that, under most conditions, NS3 protease activity is dependent on the aggregation state of the NS3/4A complex. The monodisperse, soluble form of the NS3/4A complex is associated with the highest protease activity.     

Lost: Our intelligence? Why?

The "concept of general intelligence, despite being maligned by a few, regarded as a 2nd-order function by some, and discarded or ignored by others, still has a rightful place in the science of psychology and in the practical affairs of man." "It is far from clear that tests of general intelligence have been outmoded by the multi-test batteries as the more useful predictors of school achievement." In fact some evidence suggests that "better predictions are possible via old-fashioned general intelligence tests." Discussion focuses on reasons for discarding the idea of general intelligence, factor theories of intelligence, and recent trends in the assessment of "general intelligence." "By the criterion of social usefulness, the multiple aptitude batteries have been found wanting." It is "time for the profession to establish a bureau of standards to test the tests." (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Correction to a correction.

Demonstrates that A. B. Silverstein's (see record 1970-05886-001) "corrected" version of Q. McNemar's formula for correlating short-form with full-scale scores is based on fallacious reasoning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

On so-called test bias.

Notes that when 2 groups differ in criterion performance and on a selection test, the use of the regression equation derived on the higher group tends to overestimate the mean performance of the lower group and the equation based on the lower group tends to underestimate the mean performance of the higher group. This "unfairness" is reduced somewhat by using an equation based on the groups combined. To avoid this "bias" in selection, various definitions of fairness have led to nonregression models. The present article proposes a multiple regression model which renders estimates fair in the sense that group means are accurately predicted, hence "mean-fair." This model is discussed in detail and examples of its use are presented. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

McNemar replies to Bass and Angoff.

Replies to comments by A. R. Bass (1976) and W. H. Angoff (1976). McNemar's model (see record 1975-30837-001) will satisfy H. J. Einhorn and Bass's (1971) equal risk model without the need to have a maximum risk probability that is tolerable for the institution. Also, McNemar's model reflects an unbiased expectation of performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)