Abstract: An n-hexadecane-degrading bacterium LAM0048 was isolated from hydrocarbon-polluted soil by using n-hexadecane as sole carbon source. Based on analyses of the morphological, physiological and biochemical character, cellular chemical composition, 16S rRNA sequences, strain LAM0048 was suggested to represent a member of the genus Gordonia of family Nocardiaceae, suborder Corynebacterineae. Comparative analysis of the fatty acids and polar lipid composition revealed that LAM0048T was a novel species within the genus Gordonia. Study on the degradation efficiency of strain LAM0048 with different n-hexadecane concentration indicated that strain LAM0048 was able to degrade 100% of n-hexadecane in the mineral medium containing 0.05% (V/V) n-hexadecane after 36 h incubation at 30℃, and was able to degrade 46.4% of n-hexadecane in the mineral medium containing 1.0% (V/V) n-hexadecane. The new isolate was an alkane-degrading bacterium with highly concentration of alkane tolerance ability，and may provide new insight into microbial degradation of alkane.

Key words: Gordonia sp., n-hexadecane, alkane degradation, isolation and identification, high tolerance

摘要： 以正十六烷为唯一碳源，从长期受石油污染的土壤中筛选到一株高效降解正十六烷的菌株LAM0048。通过形态学观察、生理生化试验、细胞化学组分分析、16S rRNA基因序列分析、细胞脂肪酸和极性脂试验，确定其属于棒杆菌亚目(Corynebacterineae)、诺卡菌科(Nocardiaceae)、戈登氏属(Gordonia)，且可能为戈登氏属的一株新种。采用单因素实验对菌株LAM0048在无机盐培养基中降解正十六烷的降解率进行初步探讨，发现该菌株能在以正十六烷为唯一碳源的培养基中生长，菌株LAM0048能够在36 h内完全降解0.05%(V/V)的正十六烷，当烷烃浓度达到1.0%(V/V)时，降解率达46.4%。结果表明LAM0048是一株具有耐受高浓度烷烃的石油降解菌，在石油污染环境的微生物修复中具有一定的应用潜力。

关键词: Gordonia sp., 正十六烷, 降解, 分离鉴定, 高耐受性