Identification of four genes expressed by feeding female Ixodes scapularis, including three with sequence similarity to previously recognized genes.

We created a cDNA library from feeding, female Ixodes scapularis ticks and screened the library with a subtracted probe to eliminate most genes common to feeding female and mating male I. scapularis ticks. Four unique genes were identified in this screen.

Mating, male Ixodes scapularis express several genes including those with sequence similarity to immunoglobulin-binding proteins and metalloproteases.

We created a cDNA library from mating, male Ixodes scapularis ticks and screened the library with a subtracted probe to eliminate genes common to feeding female and mating male I. scapularis ticks. A total of seven unique cDNAs were identified in this screen.

The prevalence of Borrelia burgdorfieri (Spirochaetales: spirochaetaceae) and the agent of human granulocytic ehrlichiosis (Rickettsiaceae: Ehrlichieae) in Ixodes scapularis (Acari:Ixodidae) collected during 1998 and 1999 from Minnesota.

We tested 103 adult Ixodes scapularis Say from 12 counties in Minnesota for the presence of Borrelia burgdorferi and the causative agent of human granulocytic ehrlichiosis (HGE), using polymerase chain reaction (PCR). A total of 17 ticks (16.5%) was positive for B.

New records of the blacklegged tick, Ixodes scapularis (Acari: Ixodidae) in Minnesota.

The Minnesota distribution of the blacklegged tick, Ixodes scapularis, was studied during 1998 and 1999. The majority of tick collecting was done by grouse hunters, who sent in specimens collected during the fall of 1998 and 1999. I.

A chemoattractant cytokine associated with granulomas in tuberculosis and silicosis.

Chronic inflammation and granuloma formation are associated with mononuclear cell infiltrates and are characteristic pathologic responses in tuberculosis. To identify host cell genes involved in tuberculous pathology, we screened macrophage cDNA libraries for genes induced by mycobacterial infection. One gene isolated in this screen, osteopontin (also known as early T lymphocyte activation protein 1 or Eta-1), was of particular interest because it is a cytokine and macrophage chemoattractant.

The Streptomyces glaucescens TcmR protein represses transcription of the divergently oriented tcmR and tcmA genes by binding to an intergenic operator region.

Preliminary evidence has been presented by Guilfoile and Hutchinson (J. Bacteriol. 174:3651-3658, 1992) suggesting that the Streptomyces glaucescens TcmR protein is a transcriptional repressor.

Sequence and transcriptional analysis of the Streptomyces glaucescens tcmAR tetracenomycin C resistance and repressor gene loci.

Sequence analysis of the tcmA tetracenomycin C resistance gene from Streptomyces glaucescens GLA.O (ETH 22794) identifies one large open reading frame whose deduced product has sequence similarity to the mmr methylenomycin resistance gene from Streptomyces coelicolor, the Streptomyces rimosus tet347 (otrB) tetracycline resistance gene, and the atr1 aminotriazole resistance gene from Saccharomyces cerevisiae. These genes are thought to encode proteins that act as metabolite export pumps powered by transmembrane electrochemical gradients.

A bacterial analog of the mdr gene of mammalian tumor cells is present in Streptomyces peucetius, the producer of daunorubicin and doxorubicin.

Sequence analysis of the drrAB locus from Streptomyces peucetius (American Type Culture Collection 29050) reveals the presence of two genes, drrA and drrB, both of which are required for daunorubicin and doxorubicin (Adriamycin) resistance in the heterologous host Streptomyces lividans. The DrrA protein is similar to a large family of ATP-binding transport proteins, including the proteins encoded by the mdr genes from mammalian tumor cells, which confer resistance to daunorubicin, doxorubicin, and some other structurally unrelated chemotherapeutic agents. The DrrB protein shows no significant similarity to other known proteins but is probably very hydrophobic, suggesting that it is located in the bacterial membrane.