Cloning and nucleotide sequence of senN, a novel 'Bacillus natto' (B. subtilis) gene that regulates expression of extracellular protein genes

A new 'Bacillus natto' gene, senN, that regulates the expression of several extracellular proteins in B. subtilis has been cloned and sequenced. senN codes for a small, highly basic protein with an amino acid sequence different from the products coded by the regulatory genes sacQ, sacV, prtR and hpr. SenN stimulates gene expression at the transcriptional level. A putative homologous locus has been detected in the B. subtilis chromosome by Southern blotting.

Expression and secretion of human atrial natriuretic alpha-factor in Bacillus subtilis using the subtilisin signal peptide

Using the signal peptide of the Bacillus subtilis subtilisin gene (aprE) and a synthetic cDNA corresponding to the mature region of the human atrial natriuretic alpha-factor (hANF), we have constructed a secretion vector. B. subtilis cells, when transformed with this vector, secrete immunoreactive hANF peptides into the medium at about 500 micrograms/liter. The hANF is the first human gene product to be secreted from B. subtilis using this signal peptide. We have used promoters active during vegetative growth or sporulation and hosts deficient in several extracellular proteases but some proteolysis of the secretion products still occurs. In addition, both cell growth and sporulation are adversely affected by hANF production. Possible explanations for this observation are inefficient secretion of the atrial hormone or toxicity of the precursor or mature peptide.

rpoD operon promoter used by sigma H-RNA polymerase in Bacillus subtilis

Three promoters direct transcription of the sigA (rpoD) operon in Bacillus subtilis. Promoters P1 and P2 are used during the exponential growth phase, whereas P3 is used only during the stationary phase. We examined the use of these promoters in promoter-probe plasmids and found that expression from P3 was prevented by a mutation in spoOH, which encodes the secondary RNA polymerase sigma factor sigma H. Moreover, we found that sigma H-containing RNA polymerase efficiently and accurately used the P3 promoter in vitro. Evidently, this operon, which is essential for exponential growth, is transcribed during the early phase of sporulation by this secondary form of RNA polymerase. Comparison of the nucleotide sequences of the P3 promoter and the spoVG promoter, which also is used by sigma H-RNA polymerase, revealed sequences at the -10 and -35 regions of these promoters that may signal recognition of promoters by sigma H-RNA polymerase.

Developmental expression of three proteins from the first gene of the RNA polymerase sigma 43 operon of Bacillus subtilis

The first gene of the Bacillus subtilis RNA polymerase sigma 43 operon, P23, has a protein-coding capacity of 23,000 daltons. Sequence analysis revealed three potential translational initiation sites within the same reading frame, which could encode proteins of 23,000 (P23), 19,000 (P19), and 9,000 (P9) daltons, respectively. An internal promoter (P3), which is expressed only during the sporulation stage, is located between the second and the third translational start sites. By protein fusion to the Escherichia coli beta-galactosidase gene, we showed that all three translational initiation sites of the P23 gene are used in vivo in both E. coli and B. subtilis, and regulation for differential expression of the three proteins during the development of B. subtilis is coupled to the transcriptional promoter switching mechanism. The physiological function of these multiple gene products is unknown and is currently under investigation.

Translaryngeal guided intubation for difficult intubation

Airway obstruction remains a constant problem in acute care. This is particularly true when there are anatomical or pathological abnormalities, trauma, or when repeated failed attempts at endoscopic or blind intubations have left a bloody field, preventing clear visualization of the vocal cords. Our refinement of translaryngeal guided intubation (TLI) uses a spring guidewire accompanied by a plastic sheath protector. The wire is introduced percutaneously via a cricothyroid puncture and passed cephalad into the oropharynx or nasopharynx and out through the mouth or one of the nostrils. The plastic sheath is slid over the wire into the trachea. A well-lubricated endotracheal tube is then inserted to the desired position using the plastic sheath as a stylet. This technique works very well, and we are convinced that TLI is one of the most effective emergency techniques to secure an airway. It can be performed quickly with inexpensive equipment and is a promising addition to the currently recommended alternatives.

Promoter switching during development and the termination site of the sigma 43 operon of Bacillus subtilis

Sequencing data indicated that the RNA polymerase sigma 43 operon of Bacillus subtilis consisted of three genes, P23 (function unknown), dnaE (DNA primase), and rpoD (sigma 43) (Wang and Doi 1986a). S1 nuclease mapping experiments with RNA from various stages of growth demonstrated the presence of two overlapping sigma 43 promoters that controlled the expression of the operon during growth and a sigma 37 promoter that regulated the expression of the operon during the sporulation phase. This promoter switching mechanism ensured that this important operon would be expressed during different nutritional states of the cell and also illustrated a function for the minor RNA polymerase sigma 37 holoenzyme in the expression of genes which are normally expressed during the logarithmic phase of growth. The location of the transcription termination signal confirmed that the sigma 43 operon consists of three genes.

Properties of a monoclonal antibody interacting with human sperm

A monoclonal antibody (MAB) interacting with human sperm was purified by ammonium sulfate fractionation and gel filtration on Sephadex G-200. The MAB designated as YWK-II belongs to the IgM class and is composed of mu heavy chains and kappa light chains. The MAB localized to the equatorial region of the sperm head, midpiece, and tail. The sperm antigen interacting with the YWK-II MAB was purified by immunoaffinity chromatography on Sepharose 4B conjugated with YWK-II antibodies. Two interacting proteins, estimated Mr of 60 and 72 kD, were identified.

Nucleotide sequence and organization of Bacillus subtilis RNA polymerase major sigma (sigma 43) operon

The gene coding for Bacillus subtilis RNA polymerase major sigma 43, rpoD, was cloned together with its neighboring genes in a 7 kb EcoRI fragment. The complete nucleotide sequence of a 5 kb fragment including the entire rpoD gene revealed the presence of two other genes preceding rpoD in the order P23-dnaE-rpoD. The dnaE codes for DNA primase while the function of P23 remains unknown. The three genes reside in an operon that is similar in organization to the E. coli RNA polymerase major sigma 70 operon, which is composed of genes encoding small ribosome protein S21 (rpsU), DNA primase (dnaG), and RNA polymerase sigma 70 (rpoD). There is a relatively high degree of base and amino acid homology between the DNA primase and sigma genes. The most significant differences between the two operons are observed in the molecular size of the first genes (P23 and rpsU), the complete lack of amino acid homology between P23 and S21, the molecular weights of the two rpoD genes, the size of the intercistronic region between the first two genes, and the regulatory elements of the operon.

Characterization of sperm agglutinating monoclonal antibody and purification of the human sperm antigen

A monoclonal antibody capable of inducing tail-to-tail agglutination of human sperm was purified by ammonium sulfate fractionation and chromatography on DEAE-cellulose. A 75- to 100-fold purification was achieved. The antibody was of the IgG class and composed of gamma 1 heavy chain and lambda light chains. The purified preparation was effective in inducing sperm agglutination at a minimum concentration of 0.55 microgram/mL and was active after storage at 4 degrees C for over 3 months in the presence of sodium azide. The sperm antigen interacting with this YWK-1 antibody was purified by immunoaffinity chromatography on Sepharose 4B conjugated with YWK-1 antibodies. Two interacting proteins were isolated, with estimated Mr of 84 and 20 kD. The 84 kD protein had an isoelectric point in the range of pH 5.7 to 6.1, and probably lacks carbohydrate moieties. The 20 and 84 kD components may share common antigenic determinants.

Isolation and characterization of a rabbit sperm tail protein

Rabbit sperm tails were obtained by a nitrogen cavitation procedure and separated by discontinuous sucrose gradient centrifugation. Proteins were extracted from sperm tails with 3[(3-cholamidopropyl)-dimethylammonio]-1-propane sulfonate (CHAPS) and separative disk electrophoresis and DEAE-trisacryl column chromatography. A protein with an estimated mol wt of 20.1 +/- 1.1 kD was isolated and found to be homogeneous by SDS-PAGE and designated as rSMP-B. The isoelectric point of rSMP-B was in the range of pH 4.4-4.7. The amino acid composition was determined, and glycine was identified as the N-terminal residue. Antisera were raised against purified rSMP-B. Using a peroxidase-antiperoxidase method, the rSMP-B antigen was located on the surface of the midpiece and tail of the sperm. Testis sections showed intense staining of late spermatids located within the seminiferous tubules. Adult male rabbits were inoculated with rSMP-B protein and Freund's adjuvant. The testis and epididymis of the immunized animals showed absence of sperm. The immunolocalization findings and the immunization data suggest that rSMP-B is formed in late spermatid and that it is an essential structural component of sperm.

Catabolite-resistant sporulation (crsA) mutations in the Bacillus subtilis RNA polymerase sigma 43 gene (rpoD) can suppress and be suppressed by mutations in spo0 genes

The catabolite-resistant sporulation (crsA) mutation is able to overcome the repressive effect of glucose on sporulation in Bacillus subtilis. Three chromosomal crsA mutations, crsA1, crsA4, and crsA47, were transferred by the "gene conversion" process to B. subtilis plasmid pRPD11, which consists of the entire wild-type rpoD coding sequence, encoding the major sigma 43 factor of B. subtilis RNA polymerase, and pUB110. By DNA sequence analysis we showed that all three crsA mutations were identical two-base changes, CCT (proline) to TTT (phenylalanine), within the rpoD coding sequence. Furthermore, the crsA47 mutation restored spo0J and spo0K sporulation to wild-type levels and partially improved the sporulation efficiencies of spo0B, spo0D, and spo0F. Extragenic suppressors (scr) of crsA47 included mutations in spo0A, spo0D, spo0F, and spo0K plus other mutations that have not been specifically identified. Thus sigma 43 appears to be involved in catabolite repression by glucose, to interact either directly or indirectly with spo0 gene products, and to play an important role in the initiation of spore development in B. subtilis.

A strong sequence homology exists between the major RNA polymerase sigma factors of Bacillus subtilis and Escherichia coli

The Bacillus subtilis rpoD gene has been sequenced and the primary structure of its product deduced. The molecular weight calculated for the sigma 43 is 42,828. The DNA and protein sequences of sigma 43 exhibit extensive homology to the Escherichia coli rpoD gene and its sigma 70 product, especially in the C-terminal two-thirds of the sequence. Other proteins exhibiting partial homology with sigma 43 include the E. coli nusA protein, the E. coli htpR (heat-shock regulatory gene) product sigma 32, and specific DNA-binding proteins. No amino acid homology was found between sigma 43 and B. subtilis phage SP01 sigma gp28, phage T7 RNA polymerase, or E. coli DNA primase. The gene exhibits a strong ribosomal binding site and a typical rho-independent transcription terminator sequence. A typical transcription terminator sequence was not observed upstream from the sigma 43 gene. The sigma 43 gene may be part of an operon, resembling the situation found in the E. coli sigma operon.

Bacillus subtilis dnaE encodes a protein homologous to DNA primase of Escherichia coli

Bacillus subtilis dnaE encodes a protein essential for DNA replication and is tightly linked to rpoD, the gene for the major sigma factor of RNA polymerase. We have now determined the 1809-base pair sequence of the dnaE coding region, which precedes rpoD and is transcribed in the same counterclockwise direction on the chromosome. From the DNA sequence, we found that the dnaE protein comprised 603 amino acids with a calculated molecular mass of 68,428 daltons. This protein had significant and extensive regions of homology with Escherichia coli DNA primase, the polymerase that synthesizes short RNA primers during discontinuous DNA replication. Features of the coding and flanking regions that may modulate dnaE expression include a relatively weak ribosomal binding site (delta G' = -13.8 kcal), the use of uncommon codons in the reading frame, and no obvious promoter sequence for either dnaE or rpoD. Together, these results suggest that dnaE codes for B. subtilis DNA primase and, in light of the similarities to the organization of the E. coli sigma operon, that expression of dnaE may be coregulated with rpoD in B. subtilis.

Frequencies of ceruloplasmin alleles in a Chinese population

Plasma ceruloplasmin phenotypes were determined in a Chinese population. Among 1,042 unrelated persons examined, 3 appeared to be heterozygotes for an unidentified allele. Thus the frequency of the rare ceruloplasmin allele was estimated to be 0.0014.

Immunolocalization of a sperm membrane protein in human male reproductive organs

A monoclonal antibody that induces agglutination of human sperm was used to localize the interacting antigen in various tissues by indirect immunofluorescence. The antibody localized to the immature sperm and Sertoli cells of the seminiferous tubules, simple cuboidal epithelial cells of the rete testis, and the columnar epithelial cells of the ductuli efferentes. The present results show that the interacting protein is found associated with germ cells undergoing spermatogenesis.