+ Resolve Article
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter

+ Translate
+ Subscribe to Site Feed
GeoScience Most Shared ContentMost Shared Content

In vivo evolution of the Aeromonas punctata polyhydroxyalkanoate (PHA) synthase: isolation and characterization of modified PHA synthases with enhanced activity

, : In vivo evolution of the Aeromonas punctata polyhydroxyalkanoate (PHA) synthase: isolation and characterization of modified PHA synthases with enhanced activity. Applied Microbiology and Biotechnology 59(4-5): 477-482

In vivo random mutagenesis of the polyhydroxyalkanoate (PHA) synthase gene from Aeromonas punctata was performed employing the mutator strain Escherichia coli XL1-Red. About 200,000 mutants were screened on Nile red-containing medium and five mutants with enhanced fluorescence were selected. Four of these mutants exhibited enhanced in vivo and in vitro PHA synthase activity. Mutant M1, which carried the single mutation F518I, showed a five-fold increase in specific PHA synthase activity, whereas the corresponding mediated PHA accumulation increased by 20%, as compared with the wild-type PHA synthase. Mutant M2, which carried the single mutation V214G, showed a two-fold increase in specific PHA synthase activity and PHA accumulation only increased by 7%. Overall, the in vitro activities of the overproducing mutants ranged from 1.1- to 5-fold more than the wild-type activity, whereas the amounts of accumulated PHA ranged over 107-126% of that of the wild type. Moreover, all mutants mediated synthesis of PHAs with an increased weight average molar mass, but the molar fractions of 3-hydroxybutyrate and 3-hydroxyhexanoate remained almost constant. In vivo random mutagenesis proved to be a versatile tool to isolate mutants exerting improved properties with respect to PHA biosynthesis.


PMID: 12172613

DOI: 10.1007/s00253-002-1035-3

Other references

Pan'ko, I.S., 1977: Etiology of collagenosis in fattened bull calves. Veterinariia: 80-82

Mowbray, D.N.; Paller, A.S.; Nelson, P.E.; Kaplan, R.L., 1988: Disseminated Fusarium solani infection with cutaneous nodules in a bone marrow transplant patient. Fusarium is a ubiquitous fungus that commonly colonizes ulcerated, burned, or traumatized skin and may cause keratitis and onychomycosis in healthy hosts. Serious disseminated infection due to Fusarium has been reported with increasing frequency i...

Huihui Mao; Baoshan Li; Liwen Yue; Longyao Wang; Jihe Yang; Xiaoxin Gao, 2011: Aluminated mesoporous silica-pillared montmorillonite as acidic catalyst for catalytic cracking. Mesostructured aluminosilicate intercalates have been prepared by the post synthesis grafting of aluminum onto the mesostructured interlayer space silica framework of a silica-pillared clay (SPC) precursor derived from the natural montmorillonite....

Hinuma, Shuji, 1999: Identification of novel bioactive peptides by utilizing orphan seven-transmembrane-domain receptors. Japanese Journal of Pharmacology 79(SUPPL 1): 28P

Thorson, TB.; Watson, DE., 1975: Reassignment of the African freshwater stingray, Potamotrygon garouaensis, to the genus Dasyatis. on physiologic and morphologic grounds. Copeia, 4: 701-712

Nadeau, P.; Yuan, M.; Weisgraber, K.; Yankner, B.A., 1998: Regulation of amyloid precursor protein metabolism by lipoproteins. Society for Neuroscience Abstracts 24(1-2): 1005

Haugarvoll, K.; Bindoff, L.A., 2014: A novel compound heterozygous tyrosine hydroxylase mutation (p.R441P) with complex phenotype. Tyrosine hydroxylase (TH) is a tetrahydrobiopterin (BH4) dependent enzyme that catalyses the conversion of L-tyrosine to L-dopa, the rate-limiting step in the biosynthesis of dopamine. Autosomal recessive mutations in the TH gene cause impaired TH...

Hooper, D.G.; Hirsh, D.C., 1977: Changes of resistance of enteric bacteria in mice given tetracycline in drinking water. Tetracycline given to mice via their drinking water for long periods changed the gram-negative enteric flora and increased the minimal inhibitory concentration of tetracycline for Proteus and Escherichia coli in the feces.

Galante J.; Sim F.; Kuo K.; Rostoker W.; Chao E.; Pritchard D., 1981: Segmental replacement of long bones using fiber titanium composites. Orthopaedic Transactions 5(3): 428-429

Goldman, E.A., 1938: Six new Rodents from Coahuila and Texas and notes on the status of several described forms. Proceedings of the Biological Society of Washington, 51: 55-62