Biomaterial Database

Purification and characterization of LasD: a second staphylolytic proteinase produced by Pseudomonas aeruginosa. 1995

S Park, and D R Galloway

Department of Microbiology, Ohio State University, Columbus 43210-1292, USA.

We have previously described studies of a 22 kDa active fragment of the LasA proteinase. In follow-up studies of LasA, we have discovered the separate existence of a 23 kDa proteinase which shares many of the enzymatic properties of LasA, including the ability to lyse heat-killed staphylococci. However, this apparent serine proteinase, which we designate LasD, is distinct from the 22 kDa active LasA protein for the following reasons: (i) the N-terminal sequence of LasD shares no homology with LasA or the LasA precursor sequence; (ii) Pseudomonas aeruginosa LasA mutant strains AD1825 and FRD2128 do not produce LasA yet produce LasD; and (iii) specific antibodies to each proteinase do not show any cross-reactivity. LasD appears to be produced as a 30 kDa protein, which is possibly cleaved to produce a 23 kDa active fragment. The purified LasD fragment (23 kDa) shows strong staphylolytic activity only at higher pH conditions, while LasA exhibits staphylolytic activity over a broad pH range. In addition to their ability to cleave at internal diglycine sites, both the LasD and LasA endoproteinases efficiently cleave beta-casein.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008666	Metalloendopeptidases	ENDOPEPTIDASES which use a metal such as ZINC in the catalytic mechanism.	Metallo-Endoproteinases,Metalloendopeptidase
D008969	Molecular Sequence Data	Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.	Sequence Data, Molecular,Molecular Sequencing Data,Data, Molecular Sequence,Data, Molecular Sequencing,Sequencing Data, Molecular
D010450	Endopeptidases	A subclass of PEPTIDE HYDROLASES that catalyze the internal cleavage of PEPTIDES or PROTEINS.	Endopeptidase,Peptide Peptidohydrolases
D011550	Pseudomonas aeruginosa	A species of gram-negative, aerobic, rod-shaped bacteria commonly isolated from clinical specimens (wound, burn, and urinary tract infections). It is also found widely distributed in soil and water. P. aeruginosa is a major agent of nosocomial infection.	Bacillus aeruginosus,Bacillus pyocyaneus,Bacterium aeruginosum,Bacterium pyocyaneum,Micrococcus pyocyaneus,Pseudomonas polycolor,Pseudomonas pyocyanea
D002364	Caseins	A mixture of related phosphoproteins occurring in milk and cheese. The group is characterized as one of the most nutritive milk proteins, containing all of the common amino acids and rich in the essential ones.	alpha-Casein,gamma-Casein,AD beta-Casein,Acetylated, Dephosphorylated beta-Casein,Casein,Casein A,K-Casein,Sodium Caseinate,alpha(S1)-Casein,alpha(S1)-Casein A,alpha(S1)-Casein B,alpha(S1)-Casein C,alpha(S2)-Casein,alpha-Caseins,beta-Casein,beta-Caseins,epsilon-Casein,gamma-Caseins,kappa-Casein,kappa-Caseins,AD beta Casein,Caseinate, Sodium,K Casein,alpha Casein,alpha Caseins,beta Casein,beta Caseins,beta-Casein Acetylated, Dephosphorylated,beta-Casein, AD,epsilon Casein,gamma Casein,gamma Caseins,kappa Casein,kappa Caseins
D004791	Enzyme Inhibitors	Compounds or agents that combine with an enzyme in such a manner as to prevent the normal substrate-enzyme combination and the catalytic reaction.	Enzyme Inhibitor,Inhibitor, Enzyme,Inhibitors, Enzyme
D000595	Amino Acid Sequence	The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.	Protein Structure, Primary,Amino Acid Sequences,Sequence, Amino Acid,Sequences, Amino Acid,Primary Protein Structure,Primary Protein Structures,Protein Structures, Primary,Structure, Primary Protein,Structures, Primary Protein
D001426	Bacterial Proteins	Proteins found in any species of bacterium.	Bacterial Gene Products,Bacterial Gene Proteins,Gene Products, Bacterial,Bacterial Gene Product,Bacterial Gene Protein,Bacterial Protein,Gene Product, Bacterial,Gene Protein, Bacterial,Gene Proteins, Bacterial,Protein, Bacterial,Proteins, Bacterial
D012697	Serine Endopeptidases	Any member of the group of ENDOPEPTIDASES containing at the active site a serine residue involved in catalysis.	Serine Endopeptidase,Endopeptidase, Serine,Endopeptidases, Serine