We previously reported that a gene hpcopA isolated from Helicobacter pylori is associated with copper transport. In the present study, the DNA upstream of the hpcopA was cloned and the nucleotide sequence analyzed. An open reading frame coding for 124 amino acids was predicted, which was connected in frame to the hpcopd. The deduced protein sequence exhibits striking homology with known copper-transporting P-type ATPases. Disruption of this ORF renders H. pylori hypersensitive to copper present in growth media, indicating that it encodes the N-terminal amino acid sequence of the hpCopA protein.Measurement of copper content in the wild-type and hpcopd-disrupted cells showed that the copper content was increased in the mutant cells, further supporting that the previous proposal that the gene hpcopA is involved in copper export. In addition, the cop operon consisting of the genes hpcopA and hpcopP was identified by primer extension and reverse transcriptionpolymerase chain reaction. Our results indicate that the genes for copper import and export are located in separate operons within H. pylori.

Assignments are suggested for 32 transitions in Ar VI involving doublet levels in the 3p' and 3s3p3d configurations. Beam-foil decay curves are used to measure the lifetimes of these levels, the results being systematically about 25% longer than the values calculated by Fawcett. These decays are also used in ANDC analyses of the lifetimes of the 3.13~' 2S, *P, 2D and 3?3d 'D levels, where the agreement with Fawcett's calculation is generally good. A discussion is also given of the alternative analysis of the Ar VI spectrum recently published by Lesteven-Vake et al. using recoil-ion techniques.a Configuration-interaction calculation using scaled Slater integrals [6].Analysis incorporating cascade data from 3s3p('P)3d 'P.Analysis incorporating cascade data from 3s3p('P)3d ' P , 3s3p('P)3d 2P and '0.Analysis incorporating cascade data from 3p' ' P and '0.e Analysis incorporating cascade data from 3s3d('P)3d 'F, 3s3p('P)3d 2D and 'F.

The techniques of beam-foil spectroscopy are applied to obtain measurements of the lifetimes of the 6s6p1P1, 3P1, 6s6d1D2, 3D1, 3D2, and 3D3 levels of Hg I and the 6p2P1/2, 2P3/2, 6d2D3/2, 2D5/2, and 7s2S1/2 levels of Hg II. The energy loss sustained by the ions in passing through the carbon foil is determined using an extended Doppler-shift technique. Constrained curve-fitting and arbitrarily normalized decay curve analyses are used to overcome problems caused by blending between transitions from the 6s6d1D2 and 3D1 levels of Hg I. The f values obtained from the resonance transitions are 1.14 ± 0.04 (Hg I) and 0.648 ± 0.022 (Hg II), in agreement with the trends found previously for higher Z ions in the Hg I and Au I isoelectronic sequences.

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