Erratum

In the report "Induction of hemoglobin accumulation in human K562 cells by hemin is reversible" by A. Dean et al. (24 Apr., p. 459), the second sentence in the legend for figure 1 should have read: "A stock solution of 600 microM hemin was prepared by adding 0.3 ml of 1N NaOH to 19.56 mg of hemin, and then adding 0.3 ml of 0.5M tris base, 2.5 ml of cell growth medium, and 0.35 ml of 1N HCI, and then diluting to a final volume of 50 ml with cell growth medium."     

Erratum

In table 1 of the report by M. Essex et al., "Antibodies to cell membrane antigens associated with human T-cell leukemia virus in patients with AIDS" (20 May, p. 859), the heading for columns 4 and 5 should have read "Cells positive (> 40 percent)"     

Erratum

In the report "The reservoir for HIV-1 in human peripheral blood is a T cell that maintains expression of CD4" by S. M. Schnittman et al. (21 July, p. 305), reference 10 on page 308 should have read, "K. Clouse et al., J. Immunol. 142, 431 (1989)."     

Erratum

In Table 1 of the report "Monoclonal antibody to Thy-1 enhances regeneration of processes by rat retinal ganglion cells in culture" by D. Leifer et al. (20 Apr., p. 303), the unit of measurement, micrometers, was omitted in the third column, "Mean length of processes per cell."     

Regulation of interprotein electron transfer by residue 82 of yeast cytochrome c

Yeast iso-1-cytochrome c (Cc) mutants have been constructed with Phe, Tyr, Gly, Ser, Leu, and Ile at position 82, each with Thr substituted for Cys at position 102. Their long-range electron transfer with zinc-substituted cytochrome c peroxidase (ZnCcP) has been studied by two kinetic techniques. The charge-separated complex, [(ZnCcP)+,FeIICc] converts to [ZnCcP,FeIIICc] by a single, intracomplex electron transfer step that is not governed by "gating" through possible rapid dissociation of the complex or isomerization (for example, heme-ligand) by FeIICc subsequent to its formation from FeIIICc. In every variant with an aliphatic residue at position 82 of Cc, the rate of this electron transfer process is approximately 10(4) slower at approximately 0 degrees C than for the two variants with aromatic residues.     

Side chain contributions to the stability of alpha-helical structure in peptides

Short peptides that contain significant alpha-helical structure in aqueous solution allow the investigation of the role of amino acid side chains in stabilizing or destabilizing alpha-helix structure. A host-guest system of soluble synthetic peptides was designed that consisted of chains with the block sequence TyrSerGlu4Lys4X3Glu4Lys4, denoted EXK, in which X represents any "guest" amino acid residue. Circular dichroism spectroscopy indicates that the extent of helicity of these peptides follows the order Ala greater than Leu greater than Met greater than Gln greater than Ile greater than Val greater than Ser greater than Thr greater than Asn greater than Gly. This order differs from both host-guest copolymer values (Met greater than Ile greater than Leu greater than Ala greater than Gln greater than Val greater than Thr greater than Asn greater than Ser greater than Gly) and the tendencies of these amino acids to occur in helices in globular proteins (Ala greater than Met greater than Leu greater than Gln greater than Ile greater than Val greater than Asn, Thr greater than Ser greater than Gly), but matches the order found in a series of synthetic coiled-coil alpha helices, except for Ser. Proton nuclear magnetic resonance analysis of several EXK peptides indicates that these peptides are partially helical, with the helical residues favoring the amino terminus.     

Erratum

In the Technical Comment "Trans-activator gene of HTLV-II: Interpretation" by W. C. Greene et al. (27 Feb., p. 1073), the third-from-the-last sentence should have read, "In addition, using Jurkat or other T-cell lines, Inoue and colleagues (2) and Maruyama et al. (3) have described activation of both the IL-2 receptor and IL-2 genes by the tat-I gene isolated from HTLV-I, which shares similar structural and functional properties with the tat-II gene." Reference 3 should have been to M. Maruyama et al., cell 48,343(1987).     

Nucleotide sequence of the "denaturable" leucine transfer RNA from yeast

The nucleotide sequence of " denaturable"leucine acceptor transfer RNA (tRNA(Leu)(3)) from baker's yeast was determined on (32)P-labeled material. The molecule is 85 nucleotides long and can be folded into the "cloverleaf" model for secondary structure. The basis on which the sequence was deduced from the products of complete enzymatic digestion, prior to its unambiguous determination, is presented.     

An antifungal agent inhibits an aminoacyl-tRNA synthetase by trapping tRNA in the editing site

Aminoacyl-transfer RNA (tRNA) synthetases, which catalyze the attachment of the correct amino acid to its corresponding tRNA during translation of the genetic code, are proven antimicrobial drug targets. We show that the broad-spectrum antifungal 5-fluoro-1,3-dihydro-1-hydroxy-2,1-benzoxaborole (AN2690), in development for the treatment of onychomycosis, inhibits yeast cytoplasmic leucyl-tRNA synthetase by formation of a stable tRNA(Leu)-AN2690 adduct in the editing site of the enzyme. Adduct formation is mediated through the boron atom of AN2690 and the 2'- and 3'-oxygen atoms of tRNA's3'-terminal adenosine. The trapping of enzyme-bound tRNA(Leu) in the editing site prevents catalytic turnover, thus inhibiting synthesis of leucyl-tRNA(Leu) and consequentially blocking protein synthesis. This result establishes the editing site as a bona fide target for aminoacyl-tRNA synthetase inhibitors.     

Preparation of highly labeled (32P)nucleic acids from yeasts; isolation of "denaturable" leucine acceptor transfer RNA

Culture conditions were developed that permit efficient incorporation of [(32)P]phosphate into nucleic acids of baker's yeast. RNA sufficiently labeled for sequence determination was obtained in this way. Pure "denaturable" leucine acceptor transfer RNA (tRNA(Leu)(3)) was isolated for this purpose.     

Erratum

In the report by Simpson et al., "Saturnian trapped radiation and its absorption by satellites and rings: The first results from Pioneer 11" (25 Jan., p. 411), in Fig. 1B the right hand scale of flux (for the electrons with energies > 3.4 million electron volts) should be multiplied by a factor of 10 so that the maximum flux measured by the electron current detector is 3 x 10(6) cm(-2) sec(-1). Furthermore, in reference 9, the following citation was inadvertently omitted: M. H. Acu?a and N. F. Ness, ibid., p. 444.     

深圳地区汉族人凝血因子XIII Val34Leu基因多态性研究

目的：研究深圳地区汉族人凝血因子XⅢ Val34Leu基因多态性特点．方法：应用PCR技术结合Hin6 Ⅰ酶切分析、琼脂糖凝胶电泳。研究深圳地区108名汉族人凝血XⅢ Val34Leu基因多态性特点。结果：深圳地区汉族人等位基因Val34与等位基因Leu34的频率分别为99.07％和0.93％。Val／Val纯合子、Val／leu杂合子和Leu／Leu纯合子的频率分别为98．15％,1．85％和0。结论：深圳地区汉族人凝血因子XⅢ Leu34等位基因频率比高加素人群低。     

饲料中亮氨酸和异亮氨酸交互作用对牙鲆消化酶及免疫相关酶活力的影响

为研究饲料中亮氨酸(Leucine,Leu)和异亮氨酸(Isoleucine,Ile)的交互作用对牙鲆Paralichthys olivaceus肠道消化酶及肝脏免疫相关酶活力的影响,以含50%全鱼蛋白牙鲆幼鱼饲料中氨基酸组成为参考,设2个Leu水平(分别占饲料干物质的2.58%和5.08%),并将其分别与3个Ile水平(分别占饲料干物质的1.44%、2.21%和4.44%)交互制成6种试验饲料(LL-LI、LL-MI、LL-HI、HL-LI、HL-MI、HLHI);以初始体质量为(2.69±0.04)g的牙鲆为研究对象,将其随机分为6个组,每个处理组设3个重复,分别投喂含不同Leu和Ile水平的上述6种试验饲料;60 d的流水养殖试验结束后,测定牙鲆肠道消化酶(蛋白酶和脂肪酶)及肝脏免疫相关酶(总抗氧化能力T-AOC、过氧化氢酶CAT、超氧化物歧化酶SOD、酸性磷酸酶ACP、碱性磷酸酶AKP)活力。结果表明:高Ile饲料组肠道消化酶活力显著高于中间水平Ile饲料组(P0.05),且饲料中高水平的Leu可降低肠道消化酶活力(LI组除外);在低Leu处理组,当Ile≥2.21%时,随着饲料中Ile含量的增加,肝脏中CAT、SOD、ACP和AKP活力显著提高(P0.05);但在高Leu处理组,当Ile≥2.21%时,CAT、SOD和AKP活力随饲料中Ile水平的升高显著降低(P0.05)。研究表明,Leu和Ile间存在交互作用,并显著影响牙鲆肠道消化酶及部分肝脏免疫相关酶活力,且在低Leu(2.58%)水平与高Ile(4.44%)水平(LL-HI饲料组)交互作用下,牙鲆肠道消化酶及肝脏免疫相关酶活力均为最高。     

Allelic Variation and Genetic Diversity at HMW Glutenin Subunits Loci in Yunnan,Tibetan and Xinjiang Wheat

Allelic variation and genetic diversity at HMW glutenin subunits loci, Glu-A1, Glu-B1and Glu-D1 were investigated in 64 accessions of three unique wheats of western China using sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). Two HMW glutenin patterns (i.e., "null, 7+8, 2+12" and "null, 7, 2+12") in 34 Yunnan wheat accessions, 3 HMW glutenin patterns (i.e., "null, 7+8, 2+12"; "null, 6+8, 2+12" and "null, 7+8, 2") in 24 Tibetan accessions and 1 HMW glutenin pattern ("null, 7, 2+12") in 6 Xinjiang wheat accessions were found. The Tibetan accession TB18 was found to be with a rare subunit 2 encoded by Glu-D1. A total of 4 (i.e., Glu-A1c, Glu-B1a, Glu-B1b and Glu-D1a), 5 (i.e., Glu-A1c, Glu-B1d, Glu-B1b, Glu-D1a and Glu-D1) and 3 alleles (i.e.,Glu-A1c, Glu-B1a and Glu-D1a) at Glu-1 locus were identified among Yunnan, Tibetan and Xinjiang unique wheat accessions, respectively. For Yunnan wheat, Tibetan wheat and Xinjiang wheat, the Nei′s mean genetic variation indexes were 0.1574, 0.1366 and 0,respectively, which might indicate the higher genetic diversity at HMW glutenin subunits loci of Yunnan and Tibetan wheat accessions as compared to that of Xinjiang wheat accessions. Among the three genomes of hexaploid wheats of western China, the highest Nei′s genetic variation index was appeared in B genome with the mean value of 0.2674,while the indexes for genomes A and D were 0 and 0.0270, respectively. It might be reasonable to indicate that Glu-B1 showed the highest, Glu-D1 the intermediate and GluA1 always the lowest genetic diversity.     

Correction: omitted author

Through an inadvertent error on my part, I neglected to include the name of one author-Giovina Ruberti-of the report "Requirement for CD8(+) cells in T cell receptor peptide-induced clonal unresponsiveness" (1 Jan., p. 91). The correct order of the authors is as follows: Amitabh Gaur, Giovina Ruberti, Richard Haspel, John P. Mayer, and myself.     

Corrections and clarifications

In the response by E. A. Finch and S. M. Goldin (5 Aug., p. 813) to the technical comment "Calcium and inositol 1,4,5-trisphosphate-induced Ca(2+) release" by L. Combettes and P. Champeil (5 Aug., p. 813), in parts B and C of figure 1 (p. 814), the insets referring to Ca concentrations were inadvertantly interchanged. The concentration for figure 1B should have been, "300 nM Ca" and that for figure 1C should have been, "10 nM Ca."     

Erratum

In the report "Malaria parasites adopt host cell superoxide dismutase" by A. S. Fairchild et al. (19 Aug., p. 764), the caption for figure 2 on page 765 was incorrect and should read as follows: "Comparison of host and parasite SOD's (9) by (A) polyacrylamide gel electrophoresis (8) and (B) isoelecteric focusing (7). Gels were stained for SOD activity (10), and bovine erythrocyte SOD (Sigma, type 1) was used as a reference [pI = 4.95 (13)]. Lane 1, rat-derived P. berghei SOD; lane 2, rat erythrocyte SOD (pI = 5.1); lane 3, mouse-derived P. berghei SOD; lane 4, mouse erythrocyte SOD (pl = 5.7); lane 5, bovine erythrocyte SOD." The pI's of mouse and rat erythrocyte SOD's cited in the text should also be corrected to the values given above.     

Errata for Volume 123

In the article "Pronuclear fusion as affected by x-rays and by postirradiation anaerobiosis," by C. S. Bachofer, in the issue of 27 Jan., page 139, the last sentence in column 1 should begin "The term (1/4)-fused is used to designate ...," not "The sum (1/4)-fused . . ." as printed. In the article "Magnetic techniques for in vitro isolation of leucocytes," by Sumner Levine, in the issue of 3 Feb., page 186, the equation should read micro radicaln(n+2)=4.90 Bohr magnetons, instead of as printed with the square root sign covering the last part of the equation.     

Erratum

In line 7 of the caption for table 1 (p. 1682) of the report "Association of transfer RNA acceptor identity with a helical irregularity" by William H. McClain et al. (23 Dec., p. 1679), ">/=20%" should have been "相似文献