GLORIA

GEOMAR Library Ocean Research Information Access

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Preprosubtilisin Carlsberg processing and secretion is blocked after deletion of amino acids 97-101 in the mature part of the enzyme (1991)
    Springer
    Molecular genetics and genomics 227 (1991), S. 137-143 
    Details
    ISSN: 1617-4623
    Keywords: Bacillus ; Proenzyme ; Subtilisin maturation ; Site-directed mutagenesis ; Subtilisin Carlsberg
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary During an investigation into the substrate specificity and processing of subtilisin Carlsberg fromBacillus licheniformis, two major independent findings were made: (i) as has been shown previously, a stretch of five amino acids (residues 97–101 of the mature enzyme) that loops out into the binding cleft is involved in substrate binding by subtilisin Carlsberg. In order to see whether this loop element also determines substrate specificity, the coding region for these five amino acids was deleted from the cloned gene for subtilisin Carlsberg by site-directed mutagenesis. Unexpectedly the resulting mutant preproenzyme (P42c, Mr=42 kDa) was not processed to the mature form (Mr=30 kDa) and was not released into the medium by a proteasedeficientB. subtilis host strain; rather, it accumulated in the cell membrane. This result demonstrates that the integrity of this loop element, which is very distant from the processing cleavage sites in the preproenzyme, is required for secretion of subtilisin Carlsberg. (ii) In culture supernatants fromB. subtilis harbouring the cloned wild-type subtilisin Carlsberg gene the transient appearance (at 0–3 h after onset of stationary phase) of a processing intermediate (P38c, Mr=38 kDa) of this protease could be demonstrated. P38c very probably represents a genuine proform of subtilisin Carlsberg.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00260718
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    A topological model for the haemolysin translocator protein HlyD (1992)
    Springer
    Molecular genetics and genomics 234 (1992), S. 155-163 
    Details
    ISSN: 1617-4623
    Keywords: Escherichia coli haemolysin ; Secretion of haemolysin ; Topology and function of HlyD
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary A topological model for HlyD is proposed that is based on results obtained with gene fusions of lacZ and phoA to hlyD. Active H1yD-LacZ fusion proteins were only generated when lacZ was fused to hlyD. within the first 180 by (60 amino acids). H1yD-PhoA proteins exhibiting alkaline phosphatase (AP) activity were obtained when phoA was inserted into hlyD. between nucleotides 262 (behind amino acid position 87) and 1405 (behind amino acid position 468, only 10 amino acids away from the C-terminus of HlyD Active insertions of phoA into the middle region of hlyD. were not observed on in vivo transposition but such fusions exhibiting AP activity could be constructed by in vitro techniques. A fusion protein that carried the PhoA part close to the C-terminal end of HlyD proved to be the most stable HlyD-PhoA fusion protein. In contrast to the other, rather unstable, HlyD-PhoA+ fusions, no proteolytic degradation product of this HlyD-PhoA protein was observed and nearly all the alkaline phosphatase activity was membrane bound. Protease accessibility and cell fractionation experiments indicated that the alkaline phosphatase moiety of this fusion protein was located in the periplasm as for all other HlyD-PhoA+ proteins. These data and computer-assisted predictions suggest a topological model for HlyD with the N-terminal 60 amino acids located in the cytoplasm, a single transmembrane segment from amino acids 60 to 80 and a large periplasmic region extending from amino acid 80 to the C-terminus. Neither the HlyD fusion proteins obtained nor a mutant HlyD protein that had lost the last 10 amino acids from the C-terminus of HlyD exhibited translocator activity for HlyA or other reporter proteins carrying the HlyA signal sequence. The C-terminal 10 amino acids of HlyD showed significant similarity with the corresponding sequences of other HlyD-related proteins involved in protein secretion.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00272357
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Identification and characterization of two functional domains of the hemolysin translocator protein HlyD (1994)
    Springer
    Molecular genetics and genomics 245 (1994), S. 203-211 
    Details
    ISSN: 1617-4623
    Keywords: Escherichia coli hemolysin secretion system ; HlyD protein ; HlyD-related proteins ; HlyD functional domains
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Secretion of Escherichia coli hemolysin is mediated by a sec-independent pathway which requires the products of at least three genes, hlyB, hlyD and tolC. Two regions of HlyD were studied. The first region (region A), consisting of the 33-amino acid, C-terminal part of the HlyD protein, is predicted to form a potential helix-loop-helix structure. This sequence is conserved among HlyD analogues of similar transport systems of other bacterial species. Using site-directed mutagenesis, we showed that the amino acids Leu475, Glu477 and Arg478 of this region are essential for HlyD function. The last amino acid of HlyD, Arg478, is possibly involved in the release of the HlyA protein, since cells bearing a hlyD gene mutant at this position produce similar amounts of HlyA to the wild-type strain, but most of the protein remains cell-associated. Competition experiments between wild-type and mutant HlyD proteins indicate that region A interacts directly with a component of the secretion apparatus. The second region of HIyD (region B), located between amino acids Leul27 and Leu170, is highly homologous to the otherwise unrelated outer membrane protein TolC. Deletion of this region abolishes secretion of hemolysin. This sequence of HlyD also seems to interact with a component of the hemolysin secretion machinery since a hybrid HIyD protein carrying the corresponding TolC sequence, although inactive in the transport of HlyA, is able to displace wild-type HlyD from the secretion apparatus.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00283268
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...