Streptococcus pneumoniae is among the most significant causes of bacterial disease in humans. Here we report the 2,038,615-bp genomic sequence of the gram-positive bacterium S. pneumoniae R6. Because the R6 strain is avirulent and, more importantly, because it is readily transformed with DNA from homologous species and many heterologous species, it is the principal platform for investigation of the biology of this important pathogen. It is also used as a primary vehicle for genomics-based development of antibiotics for gram-positive bacteria. In our analysis of the genome, we identified a large number of new uncharacterized genes predicted to encode proteins that either reside on the surface of the cell or are secreted. Among those proteins there may be new targets for vaccine and antibiotic development.

We describe the molecular cloning of a cDNA encoding a human brain Na+‐dependent inorganic phosphate (Pi) cotransporter (hBNPI). The nucleotide and deduced amino acid sequences of hBNPI reveal a protein of 560 amino acids with six to eight putative transmembrane segments. hBNPI shares a high degree of homology with other Na+‐dependent inorganic Pi cotransporters, including those found in rat brain and human and rabbit kidney. Expression of hBNPI in COS‐1 cells results in Na+‐dependent Pi uptake. Northern blot analysis demonstrates that hBNPI mRNA is expressed predominantly in brain and most abundantly in neuron‐enriched regions such as the amygdala and hippocampus. Moderate levels of expression are also observed in glia‐enriched areas such as the corpus callosum, and low levels are observed in the substantia nigra, subthalamic nuclei, and thalamus. In situ hybridization histochemistry reveals relatively high levels of hBNPI mRNA in pyramidal neurons of the cerebral cortex and hippocampus and in granule neurons of dentate gyrus. The level of hBNPI mRNA is quite low in fetal compared with adult human brain, suggesting developmental regulation of hBNPI gene expression. Southern analyses of nine eukaryotic genomic DNAs probed under stringent conditions with hBNPI cDNA revealed that the hBNPI gene is highly conserved during vertebrate evolution and that each gene is most likely present as a single copy. Using fluorescent in situ hybridization, we localized hBNPI to the long arm of chromosome 19 (19q13) in close proximity to the late‐onset familial Alzheimer's disease locus.

The skeleton has the ability to alter its mass, geometry, and strength in response to mechanical stress. In order to elucidate the molecular mechanisms underlying this phenomenon, differential display reverse transcriptase-polymerase chain reaction (DDRT-PCR) was used to analyze gene expression in endocortical bone of mature female rats. Female Sprague-Dawley rats, approximately 8 months old, received either a sham or bending load using a four-point loading apparatus on the right tibia. RNA was collected at 1 h and 24 h after load was applied, reverse-transcribed into cDNA, and used in DDRT-PCR. Parallel display of samples from sham and loaded bones on a sequencing gel showed several regulated bands. Further analysis of seven of these bands allowed us to isolate two genes that are regulated in response to a loading stimulus. Nucleotide analysis showed that one of the differentially expressed bands shares 99% sequence identity with rat osteopontin (OPN), a noncollagenous bone matrix protein. Northern blot analysis confirms that OPN mRNA expression is increased by nearly 4-fold, at 6 h and 24 h after loading. The second band shares 90% homology with mouse myeloperoxidase (MPO), a bactericidal enzyme found primarily in neutrophils and monocytes. Semiquantitative PCR confirms that MPO expression is decreased 4- to 10-fold, at 1 h and 24 h after loading. Tissue distribution analysis confirmed MPO expression in bone but not in other tissues examined. In vitro analysis showed that MPO expression was not detectable in total RNA from UMR 106 osteoblastic cells or in confluent primary cultures of osteoblasts derived from either rat primary spongiosa or diaphyseal marrow. Database analysis suggests that MPO is expressed by osteocytes. These findings reinforce the association of OPN expression to bone turnover and describes for the first time, decreased expression of MPO during load-induced bone formation. These results suggest a role for both OPN and MPO expression in bone cell function.

The Lewis acid promoted addition of functionalized allylstannanes A9, CIO, and Cl 1 to a variety of conjugated aldehydes was examined as a possible route to acyclic precursors of macrocyclic diterpenoids. Additions to crotonaldehyde proceeded as expected, giving the erythro adduct 1 with BF3 catalysis and the threo adduct 2 with a premixed TiCl4-stannane complex at -78 °C. Attempted additions of allylstannanes to the /3-substituted crotonaldehydes B5 and geranial (B6), on the other hand, failed completely, giving either recovered starting material at low temperature (-78 to -30 °C) or extensive decomposition at higher temperatures. The acetylenic aldehyde A3 and the /3-iodo-substituted crotonaldehyde A7, however, showed normal reactivity with allylstannanes affording adducts 3-14. The steric course of these reactions was confirmed through conversion of the adducts D3 and D4 to the -lactones D9 and D10 via rhodium-catalyzed carbonylation and oxidation. These lactones showed NMR coupling patterns consistent with the assigned stereochemistry.The coupling of allylstannanes with aldehydes has re-focused on stereochemical and mechanistic aspects of the ceived considerable attention recently, much of which has reaction.1 Yamamoto's pioneering work showed that the 0022-3263/86/1951-0863$01.50/0 © 1986 American Chemical Society chstetler, Givaudan Corporation, Clifton, NJ. We thank the South Carolina Regional Nuclear Magnetic Resonance Center for cooperation in securing high-field NMR spectra.

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