Evaluation of non-cyanobacterial genome sequences for occurrence of genes encoding proteins homologous to cyanophycin synthetase and cloning of an active cyanophycin synthetase from Acinetobacter sp. strain DSM 587.
All publicly accessible microbial genome databases were searched for the occurrence of genes encoding proteins homologous to the cyanophycin synthetase (CphA) of Synechocystis sp. strain PCC 6803 in order to reveal the capability of microorganisms not belonging to the cyanobacteria to synthesize cyanophycin. Among 65 genome sequences, genes homologous to cphA were found in Acinetobacter sp. strain ADP1 (encoding a protein homologous to CphA with 40% amino acid identity), Bordetella bronchiseptica strain RB50 (39%), Bordetella pertussis strain Tohama I (39%), Bordetella parapertussis strain 12822 (39%), Clostridium botulinum strain ATCC 3502 (39%), Desulfitobacterium hafniense strain DCB-2 (38%) and Nitrosomonas europaea strain ATCC 25978 (37%). The gene homologous to cphA from Acinetobacter sp. strain DSM 587 was amplified by PCR, ligated to the vector pBluescript SK(-) downstream of the lac promoter and introduced into Escherichia coli. The recombinant strain of E. coli expressed CphA activity at up to 1.2 U/mg protein and accumulated cyanophycin to up to 7.5% of the cellular dry matter, indicating that CphA of Acinetobacter sp. strain DSM 587 is functionally active. In Acinetobacter sp. strain DSM 587 itself, cyanophycin accumulated to up to 1.4% of the total protein under phosphate-limited conditions, and cyanophycin synthetase activity was detected, which indicated the function of cyanophycin as a storage compound in this strain.
Krehenbrink
Martin
M
Institut für Mikrobiologie, Westfälische Wilhelms-Universität Münster, Corrensstrasse 3, 48149 Münster, Germany.
Oppermann-Sanio
Fred-Bernd
FB
Steinbüchel
Alexander
A
D000150:Acinetobacter / Q000737:chemistry / Q000145:classification / Q000201:enzymology* / Q000235:genetics*; D000595:Amino Acid Sequence; D001426:Bacterial Proteins; D003001:Cloning, Molecular; D030541:Databases, Genetic; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics; D015870:Gene Expression; D005798:Genes, Bacterial / Q000235:genetics; D016680:Genome, Bacterial; D008969:Molecular Sequence Data; D016366:Open Reading Frames / Q000235:genetics; D010453:Peptide Synthases / Q000737:chemistry / Q000235:genetics*; D010802:Phylogeny; D010940:Plant Proteins / Q000302:isolation & purification / Q000378:metabolism; D017386:Sequence Homology, Amino Acid
D001426:Bacterial Proteins; D010940:Plant Proteins; C024250:cyanophycin; D010453:Peptide Synthases; C113257:cyanophycin synthase, bacteria