Rhodococcus sp. strain TM1 plays a synergistic role in the degradation of piperidine by Mycobacterium sp. strain THO100.
Mycobacterium sp. strain THO100 and Rhodococcus sp. strain TM1 were isolated from a morpholine-containing enrichment culture of activated sewage sludge. Strain THO100, but not strain TM1, was able to degrade alicyclic amines such as morpholine, piperidine, and pyrrolidine. The mixed strains THO100 and TM1 showed a better growth on piperidine as the substrate than the pure strain THO100 because strain TM1 was able to reduce the level of glutaraldehyde (GA) produced during piperidine degradation. GA was toxic to strain THO100 (IC(50) = 28.3 microM) but less toxic to strain TM1 (IC(50) = 215 microM). Strain THO100 possessed constitutive semialdehyde dehydrogenases, namely Sad1 and Sad2, whose activities toward succinic semialdehyde (SSA) were strongly inhibited by GA. The two isozymes were identified as catalase-peroxidase (KatG = Sad1) and semialdehyde dehydrogenase (Sad2) based on mass spectrometric analyses of tryptic peptides and database searches of the partial DNA sequences of their genes. In contrast, strain TM1 containing another constitutive enzyme Gad1 could oxidize both SSA and GA. This study suggested that strain TM1 possessing Gad1 played a synergistic role in reducing the toxic and inhibitory effects of GA produced in the degradation of piperidine by strain THO100.
Kim
Yong-Hak
YH
School of Biological Sciences, Seoul National University, San 56-1 Shinrim, Kwanak, Seoul 151-747, Republic of Korea. yhkim660628@hotmail.com
Kang
Un-Beom
UB
Konishi
Kyoko
K
Lee
Cheolju
C
D000588:Amines / Q000378:metabolism; D000595:Amino Acid Sequence; D001673:Biodegradation, Environmental / Q000187:drug effects; D002384:Catalysis / Q000187:drug effects; D005976:Glutaral / Q000378:metabolism / Q000494:pharmacology; D008969:Molecular Sequence Data; D015394:Molecular Structure; D009025:Morpholines / Q000378:metabolism; D009161:Mycobacterium / Q000235:genetics / Q000378:metabolism*; D010880:Piperidines / Q000378:metabolism*; D011759:Pyrrolidines / Q000378:metabolism; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012240:Rhodococcus / Q000235:genetics / Q000378:metabolism*; D012722:Sewage / Q000382:microbiology; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D050644:Succinate-Semialdehyde Dehydrogenase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism
D000588:Amines; D009025:Morpholines; D010880:Piperidines; D011759:Pyrrolidines; D012336:RNA, Ribosomal, 16S; D012722:Sewage; C032727:piperidine; C037574:morpholine; D050644:Succinate-Semialdehyde Dehydrogenase; C032519:pyrrolidine; D005976:Glutaral