title: Metabolic pathway for a new strain Pseudomonas synxantha LSH-7': from chemotaxis to uptake of n-hexadecane.
abstract: Bacteria can use n-hexadecane as a carbon source, but it remains incompletely understood whether n-hexadecane is transformed into metabolic intermediates prior to cellular uptake or not. We newly isolated a strain identified as Pseudomonas synxantha LSH-7' and conducted chemotaxis experiment of this bacterial strain towards n-hexadecane, hexadecanol and hexadecanoic acid with qualitative assays respectively. Furthermore, we described the identification of extracellular alkane hydroxylase and alcohol dehydrogenase activity; acidification of the culture medium; identification of hexadecanoic acid in the culture medium by the GC-MS analysis; and variation concentration of intracellular n-hexadecane and hexadecanoic acid. A detailed analysis of the experimental data revealed the chemotaxis of this bacterial strain towards n-hexadecane instead of its metabolic intermediates. Our results further suggested that only a fraction of total n-hexadecane followed this path, and alkane hydrolase and hexadecanol dehydrogenase were constitutively expressed when grown in the medium of n-hexadecane. Most strikingly, we quantitatively investigated the concentration of n-hexadecane adsorbed by bacterial chemotaxis. Our findings provided an original insight n-hexadecane might be converted to hexadecanoic acid extracellularly before it was taken up across the cell membrane.
authors.affiliation: Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100, China.|College of Chemistry &Chemical Engineering, Ocean University of China, Qingdao 266100, China.
authors.forename: Long
authors.initials: L
authors.lastname: Meng
authors.affiliation: Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100, China.|College of Chemistry &Chemical Engineering, Ocean University of China, Qingdao 266100, China.
authors.forename: Haoshuai
authors.initials: H
authors.lastname: Li
authors.affiliation: Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100, China.|College of Chemistry &Chemical Engineering, Ocean University of China, Qingdao 266100, China.
authors.forename: Mutai
authors.initials: M
authors.lastname: Bao
authors.affiliation: Key Laboratory of Marine Spill Oil Identification and Damage Assessment Technology, North China Sea Environmental Monitoring Center, State Oceanic Administration, Qingdao 266033, China.
authors.forename: Peiyan
authors.initials: P
authors.lastname: Sun
mesh_terms: D000426:Alcohol Dehydrogenase / Q000032:analysis; D000473:Alkanes / Q000378:metabolism*; D001692:Biological Transport; D002244:Carbon / Q000378:metabolism; D002633:Chemotaxis; D003470:Culture Media / Q000737:chemistry; D042926:Cytochrome P-450 CYP4A / Q000032:analysis; D008401:Gas Chromatography-Mass Spectrometry; D006863:Hydrogen-Ion Concentration; D053858:Metabolic Networks and Pathways; D019308:Palmitic Acid / Q000378:metabolism; D011549:Pseudomonas / Q000201:enzymology / Q000235:genetics* / Q000302:isolation & purification / Q000502:physiology*
chemical_list: D000473:Alkanes; D003470:Culture Media; D019308:Palmitic Acid; D002244:Carbon; D000426:Alcohol Dehydrogenase; D042926:Cytochrome P-450 CYP4A; C007932:n-hexadecane